Problems with fuel supply.

[ZeroLux]

Hey guys, trying to figure out what is wrong with my 89 LX-i still, and I have a few new ideas. I'll give a basic description of what's going on.

I cannot take the car at high speeds for any prolonged amount of time. Let's say I hit the highway doing over 55mph, after about 3-4 miles the car starts getting hard to keep at speed. Pressing the gas pedal does not help much unless the transmission kicks down and that only happens momentarily before it goes back to higher gear. If I try to maintain speed for much longer after the engine starts to bog I typically wind up with what sounds like detonation chatter from the valves in the chamber, usually followed by dark colored smoke coming from the exhaust. If I leave the highway and sit idle for a minute or two at a red light everything sounds normal, when I set off from the light however I get more brief chatter and more smoke and very little power for a few seconds and then the car clears up and drives right.

I recently replaced the water pump and in the process of doing so disconnected by mistake a hose that was in my way that at the time I thought was the fuel supply line. Turns out from reading the FSM a while ago it looks like the return line. It's on the drivers' side of the fuel rail and was a larger rubber hose coming out of a regulator that pointed down. When I disconnected this, the fluid coming out of it wasnt clear. It had a milky white color to it. I thought this was fairly odd but being that the fuel system wasn't my focus at the time (my shredded water pump pulley and dead pump were) I let it go.

I recently checked the catalytic converter and it was clear so it's not the cause of losing power on the highway. I thought I might have been getting too much exhaust back pressure since it occasionally feels like my EGR valve is either opening at the wrong time, too often, or being forced open by another source.

I did some work to her last week and noticed that vacuum line #12 had a cut in it. The hose was located between the throttle body and the canister by the squidbox. I taped the line shut and used a ziptie around the tape to keep it closed before I can replace the line.

My gas mileage is also pretty bad right now, on a fill up this week I got slightly over 230 miles to the tank. Normally this would have been much higher. If the smoke coming out the back is dark would that usually mean there's too much gas or too much air being spent?

I am wondering if the problem could be related to any of the following:

* Bad fuel filter
* Bad Bypass Valve
* Something (condensation/water) entered the #12 line and has jammed it
* A sensor problem I have not found yet

The car has had this problem since I got it and I don't know what the previous owner had done to it over the years, so this problem is not new. This car also has had NO mods done to it beyond repairing various parts with OE or close to OE replacements.

Any information would be very helpful. This car is starting to drive me nuts with the way it runs. :banghead:

Thanks!
Zero

EDIT: There are also no codes being thrown from the computer, I checked that a couple of days ago. I did reset it by pulling the clock fuse about a month ago when I did some other work to it though.

I have also done the following repairs to it in the last few months:
New alternator
New water pump
New dist cap
New dist rotor
New NGK plugs
New NGK wires
Two new O2 sensors installed
Seafoam via the brake booster line
Techron on a full tank of 89 grade gas

[bank2me]

EGR Valve maybe? I'd check it for sure man.

[2oodoor]

hate to say it but it sounds like a head gasket, mine did that exact thing one time and never overheated either. It was cutting up so bad one day on the way home from work, it would go up to 70 -80 mph but that is it. Pinging and carrying on, I stopped driving it, then when I tore it down I saw the gasket blown. How long has it been running like that, if it has been weeks then likely is not a head gasket or it would be overheating.

Other things to look in to would be distributor shaft and advance mechanisms condition. Fuel pressure regualtor, but did you say you had a carb or FI? You said return line so I assume FI. EGR would not slow you down that bad, those usually are problems for idle speeds.

[cygnus x-1]

By dark smoke you mean black? Like what you would see coming from an old diesel truck? That means it's burning too much fuel. Since you already replaced the O2 sensor I would guess maybe a sticky fuel injector or bad MAP sensor. More likely a sticky injector since a bad MAP sensor would probably trip a code. You can try running some fuel injection cleaner through and see if that helps. Otherwise get some extra injectors from a junkyard and try swapping them out one at a time.

C|

[ZeroLux]

Yeah I was thinking about hitting up the local pick-n-pull tomorrow to see what I can figure out part-wise on this thing. I don't think it's the head gasket though. Car has not overheated and has done this since I got it about 5 months ago. She's always run bad in some way shape or form and I'm still trying to hammer out the problems. I got most of the issues solved but this one persists. I've already run Techron in the tank and Seafoamed it by way of the manifold vacuum off the brake booster line. I was thinking the black smoke was a fuel issue too, which is what prompted me to change the O2's, but I have to wonder if it's getting enough air when it's running like that? The car overall seems to be running rich all the time. New air filter was installed after I got it and is routinely checked. From what I can tell- and I cant say all this for certain- the previous owner looks to have had some intake work done (completely replaced is what it looks like, or reman'd) not too long ago. New(ish) injectors, intake is nice and clean. I dont want to rip into the engine just yet especially how the engine itself mechanically sounds great. What other reasons would I be getting too much fuel/not enough air that I can try to diagnose this weekend?

Thanks a ton guys, the help is very appreciated.

Zero

[ZeroLux]

Fuel pressure regualtor, but did you say you had a carb or FI? You said return line so I assume FI. EGR would not slow you down that bad, those usually are problems for idle speeds.

Yeah it's injected, LX-i model A20A3 engine.

Zero

[ZeroLux]

Also I remember reading something a while back on another forum about the possibility of one of the two coolant temp sensors being in the chain of command to tell the PCM how to set the air/fuel mix- could this be part of the problem at all?

Zero

[Dr_Snooz]

I'll confess that I'm stumped. It really, really sounds to me like an exhaust restriction, possibly an intake restriction.

Random thoughts:

Did the Seafoam help at all?

I wonder if they buggered the intake installation somehow, put the wrong manifold on, stashed their crack pipes in there or whatever.

I'd look over the entire air supply/exhaust system looking for anything out of the ordinary. Look up the tailpipe, bang on the pipe, muffler, etc. Look for some kind of sound indicating a blockage. Pull off the air filter housing, look it over, look in the intake plenum as far as you can see, etc., etc., etc.

Not sure if you have the manual, but if you don't, get it and start testing any module that springs to mind. You're bound to find something bad. Start with your MAP sensor, atmospheric pressure sensor and speed sensors as they have the biggest impact on running performance. Please, please, please don't just replace random parts because they might be causing the problem. You'll be into big money fast and won't have anything to show for it. The manual has good diagnostics for everything.

The temp sensor usually causes a warm start problem, not a running problem.

Please keep us posted, I'd like to know what you learn.

Good luck!

[Oldblueaccord]

Unhook something and casue the computer to throw a code like the map sensor. I wonder if the ECM is not functioning properly.

Also is the car coming up to operating temp. making heat etc? The temp guage should be at least 1/4 of the way up.

EGR has little to do with how a car runs over all esp rich or lean.


wp

[ZeroLux]

Yeah the car reaches operating temp just fine. TBH- it drives like a car running rich, is the best way I can say it. No power, sluggish, difficult to drive really. I thought about the ECM too, and it has thrown codes before but only for the EGR valve and it does not say it all the time, maybe once a month if that many. I thought it was a plugged exhaust somewhere too but I have yet to find it. I DO get an odd pulse from the exhaust pipe though, feels like pop pop pop (x3) pause pop pop pop pop (x3) over and over again. It's not a misfire I checked for that too. It just seems like something is jammed somewhere. That's why I had the cat checked. Is there any way using trickery or anything to FORCE the car to run a certain mixture?

Thanks for the suggestions, I'll try to piss it off more in the morning and see if it barfs on me.

Zero

[cygnus x-1]

Every indication says it's getting too much fuel. I would check that coolant temp sensor for sure. That would definitely make it run rich.

C|

[Demon1024]

2x temp sensor---^
if you got white goo in your lines drain your tank and change both the filters
maybe plugged return line? as fun as it sounds you can blow into the hose and hear it in the tank to check :) take off the gas cap first tho

[ZeroLux]

Which of the two sensors is the one that dictates the fuel mix? There are two close to the throttle body on my intake, and if i remember right one has a green plug with two wires (passenger side) and the other has a yellow plug with two wires (drivers side). I checked the one with the green plug and did not find any problems but didn't take the other one out yet. I have the 995 page FSM for this car and it's been helpful but calls for tools and test harnesses that I don't have. Is there another way to test the MAP sensor without the test cable they talk about? As far as an airway constriction what would be a good way to test out the intake itself? If I am reading the FSM right the diagram for the intake looks like it has two chambers to it, on is open for the primary airflow and it looks like there's a vacuum actuated arm attached to the bypass valve that opens a second chamber for more airflow at higher speeds (?). I probably have that wrong or backwards but it's a start. What if that part is not opening the way it should? I am much more familiar with Neons than with Hondas so if this sort of thing had happened to my Dodge I would typically know right where to look. I am trying to apply what I know of it to this car but the design is completely different in it's operation.

Zero

[Oldblueaccord]

http://www.3geez.com/forum/showthread.php?t=60400

TW sensor. but the pictures are down that needs to be updated.

I think the MAP is 0-5 volts. Most of the other sensors read a resistance based on temps.

EGR code does seem to reset itself I have found. It prolly is bad but over all should not make a big differance unless it makes the EM run in "limp home" mode.

Only other thing might be to look at the ECM. some people have had a water leak lead to corrosion on the case and ground giving some wierd errors.


The pop pop at idle is normal on my car as well sounds like a misfire from the back end but other wise normal condition. Changing the coil may help this. Remember there is no tail pipe on the muffler so cold air runs into the muffler.

wp

[ZeroLux]

OK, I read the link oldblue posted above and it confirmed what I had been suspecting as being part of the problem before. Now, here's my question. I tried this tonight. I got in the car, drove a bit till it was at operating temperature and stopped at a gas station to try out the paper clip trick. Got it installed looked good, got in and started up the car. It instantly flagged the check engine light. So as opposed to trying to drive it that way and potentially running the car lean instead of rich (I prefer the lesser of the two evils and will stick with rich for the moment), I turned the car back off and removed the jumper from the plug for the TW sensor. Plugged it back into the sensor as normal and restarted the car with no CEL on the dash. I did not get the chance to poll the codes out of the ECM yet but if it's the type to retain problem codes I'm sure it will be there in the morning too. Was this an expected reaction? The post didn't go too far into the specifics of that part, just suggested the jumpering (or at least I think I interpereted it right and pulled the plug socket off the TW sensor and jumped the two wires inside with a properly fitting metal piece) to bypass the TW sensor's incorrect reading. Any thoughts?

You guys have been great through this, If this were the Neons forums I'm used to, there would have been nothing but flaming and sarcasm from a bunch of judgmental pricks.

Thanks a ton again!

Zero

[Dr_Snooz]

The MAP sensor diagnostic procedure begins on p. 12-22 of your manual. You can do the procedure up to the test harness portion and see if you learn anything from that. Looking at that test harness, it looks like it just keeps the wires all connected so you can measure voltages passing through the circuit. Up until this point, you've just been measuring potential voltages. You are ensuring that power is available, but not that it's flowing. Anyway, you're measuring voltages between color coded wires. The schematics at the back of the manual will tell you where those wires go. If you figure that out, you can probably figure out what the test harness is testing and how to get around buying one.

Having said that, I'm reluctant to point to most of these sensors because they will give you a CEL if they go bad. I've never heard of a 3g MAP sensor going bad. Nevertheless, testing them is free, so you may as well.

My money is still on a restriction of some kind. Right now, I'm trying to figure out why you have a new intake manifold. Replacing the intake on a 3g is a tremendous amount of work. You'd need a real good reason to do that and I'm at a loss to understand it. You know the car and the previous owner better than I do, what do you think was going on? That could tell you a lot right there.

As for the flaming, our cars are awesome and we know it. No need to flame to make ourselves feel better.

Again, please keep us posted as to the outcome. Thanks!

[ZeroLux]

No man, thank you. I thought a MAP sensor going bad sounded a bit uncommon to me as well, since I've worked with other cars using the same thing and they are solid state and I have yet to see one ever go bad (the Neon has one). I am leaning quite a bit towards that TW sensor at the moment but it seems finding one isn't going to be easy. I went to the boneyard today and scavenged but came up with nothing- interestingly, all the TW sensors on ALL the similar model Honda's I found out there were- uhm- gone.

I'll tell you what I would like to do though, let me take some pictures early in the AM of the way my engine looks. Everyone I have spoken to about the car that knows a bit about Honda's in general always comment on the cleanliness of the intake, alternator, and water pump. All of which are recent. From what I was told, the intake was rebuilt a couple of years ago but I am not certain as to why.

Truth be told, I got the car from a buddy of mine locally whom only had it for about eight months before buying an '08 Civic SI 6spd (is there an emoticon for drools?) and HE in turn got it from the ORIGINAL owner who bought it back in '89. The original owner is the one that had the intake rebuilt, he was a client of my friend's at the shop he worked at and my friend was relatively familiar with the history of the car. Unfortunately he didn't know the specifics behind the intake change. I do have two small leaks on both driver's side injectors but it's due to the O rings and nothing more so there's a bit of stuff around them. Maybe from the pictures someone might get a better idea of what I am looking at on my end.

To be fair about the Neon forum, I <3 my Dodge. Always have. She will run again one day, but that's another story. Unfortunately some of the members of that place have a bit of a god complex when it comes to Mopar and as such developed quite the ego towards 'lesser' people in their opinions.

Zero

[ZeroLux]

So I went this morning and warmed up the car to test out the TW sensor. According to the FSM I downloaded on page 12-26/27 the proper ohm range for a working sensor is between 200 and 400 ohms resistance. I checked the voltage coming out of the socket in the harness for the 5v it needed and it was correct so my wiring appears to be fine. However, I did find that at operational temp the sensor was only giving a value of just under 150 ohms resistance. This seems to function by way of lowering the voltage from the 5v source in the harness to the ECM unit to tell the car that it's warmed up. If the resistance was only 150 ohms I am guessing it would be feeding too much voltage back to the ECM and keeping the car in a rich status. Now, when I tried the paper clip trick I instantly got a CEL warning on the dash. After thinking on it I realize that the metal jumper used as a temporary fix would in fact be providing NO ohms resistance (or extremely little at least) thus making the car think it was running COLD. Now, if I were to go to RadioShack and find a 1/4 watt resistor with a value between 200 and 400 ohms and jump THAT into the socket instead of a paper clip I would imagine the voltage drop would properly tell the car that the engine is warm. This won't be a permanent solution since I would think that starting the car with it in place would make the ECM think it's already warm when in fact it's not and not feed enough fuel into the chambers.

Thoughts anyone?

Zero

[Dr_Snooz]

I'm assuming you had the car at operating temp, right? If so, your sensor is bad.

I wouldn't try to jury-rig it. I got mine from Napa. If they can't help you, hit the dealer.

[ZeroLux]

I'll use it as a temporary measure. I put in a 330 ohm 1/4 watt resistor and taped it down with electrical tape when the car was at operating temp. Seemed to help quite a bit but I know it's not a great idea to leave it there. When the car is cold I'll be reconnecting the old sensor then if it starts aggravating me again I'll use the resistor trick again. NAPA has this sensor available? Everywhere I've checked locally so far are clueless to it's existence and just want to sell me the other sensor. I never remember NAPA is around though, I'll have to give them a call. Thanks for the info!

Zero

[ZeroLux]

Hey would you happen to know the part number for the NAPA one? I checked their website and I see listings for about 6 or 7 sensors all claiming to be the same thing.

Zero

[cygnus x-1]

Sounds like you're on the right track. One trick with NAPAs website though, use the PartsPro SE catalog link and search that way. The rest of the site is just a PITA.

The resistor trick is not so bad really. If you wanted to get really fancy you could get a couple different value resistors and a switch. Then you have one for cold and one for warm. Ok, maybe that's just silly. :lol:

One other thing that occurred to me, are the secondary intake ports actually opening up? If they aren't it would cause an intake restriction when you get on the gas. I'm not all that familiar with that intake but there should be an actuator on the side somewhere.

C|

[ZeroLux]

No, not silly, I was considering setting up a potentiometer to do on the fly fuel control actually :P Switched between stock sensor (once I replace it, NAPA has it but I am broke at the moment) and the variable resistor tuned to provide 200-400 ohms. And I was wondering about the secondary intake ports too, the lever on the driver's side that actuates it by vacuum moves freely but when I move it by hand with the engine off, I get a 'squishy' sound.

As soon as I figure out where the heck I put my vacuum gauge I'll give it a test and see what happens. It seems as if more than one problem is currently effecting the car so I'm just narrowing my way down through it all little by little.

Oh yeah- starting the car this morning forgetting I had the resistor installed... bad idea :) WHIR WHIR WHIR PUTT stop... "OOPS! stupid me" reconnected the sensor and it fired right up.

Thanks for the direction and support guys!

Zero

[1987AccordLx-i]

Sounds like you're on the right track. One trick with NAPAs website though, use the PartsPro SE catalog link and search that way. The rest of the site is just a PITA.

The resistor trick is not so bad really. If you wanted to get really fancy you could get a couple different value resistors and a switch. Then you have one for cold and one for warm. Ok, maybe that's just silly. :lol:

One other thing that occurred to me, are the secondary intake ports actually opening up? If they aren't it would cause an intake restriction when you get on the gas. I'm not all that familiar with that intake but there should be an actuator on the side somewhere.

C|

the only way i see him checking the secondaries is under load.. i have no clue if they open up in neutral.. but sticky secondaries sounds like something that would mess with a/f readings

EDIT: zero beat me by a few mins haha.. so its not secondaries?

[Oldblueaccord]

The secondaries only come on after 5500 rpm but by the book they can be test in neutral. Open or close shouls make little differance.

The paperclip deal i never understood either I dont see how that would work but my is got the right resistance if its a small one ? :stick:

I have a pot I was going to setup with my wideband o2 sensor but I just am getting around to it this month.


wp

[ZeroLux]

EDIT: zero beat me by a few mins haha.. so its not secondaries?

I dunno, could be secondaries. I'm still a bit of a novice when it comes to this car and as far as I can remember I've never owned a car before that was configured in such a way. I saw the diagram in the FSM and it got me thinking, of course the second half of a rich problem being too little air delivery and I know everything up until the TB is clear and the filter is good. So if those arent opening I suppose it could be an issue.

They open at 5000/5500rpm? Seems like a bit of a wasted idea in an automatic. I unfortunately can't take the car that high unless I rev it in N or P, since it's so damned slow and problematic I don't want to get up on her like that in drive.

Just went out and bought a new vacuum gauge since I think I left my old one in the junkyard over the weekend :dunno: .

Anything else I should check for, sensor or vacuum wise next time I get the itch to climb under the hood?

Zero

[1987AccordLx-i]

I dunno, could be secondaries. I'm still a bit of a novice when it comes to this car and as far as I can remember I've never owned a car before that was configured in such a way. I saw the diagram in the FSM and it got me thinking, of course the second half of a rich problem being too little air delivery and I know everything up until the TB is clear and the filter is good. So if those arent opening I suppose it could be an issue.

They open at 5000/5500rpm? Seems like a bit of a wasted idea in an automatic. I unfortunately can't take the car that high unless I rev it in N or P, since it's so damned slow and problematic I don't want to get up on her like that in drive.

Just went out and bought a new vacuum gauge since I think I left my old one in the junkyard over the weekend :dunno: .

Anything else I should check for, sensor or vacuum wise next time I get the itch to climb under the hood?

Zero

im just going to throw a wild guess into this... timing? i heard that could have some effect on performance.. but when my ECT sensor went out.. i had horrible idle and it was always running rich.. its a pretty expensive part though

[ZeroLux]

im just going to throw a wild guess into this... timing? i heard that could have some effect on performance.. but when my ECT sensor went out.. i had horrible idle and it was always running rich.. its a pretty expensive part though

Ah yes, which brings me to my next question. Uhm, how? I've been told I'll need a timing light for that but it's been ages (not since my 63 Beetle) since I've used a timing light.

Zero

[1987AccordLx-i]

Ah yes, which brings me to my next question. Uhm, how? I've been told I'll need a timing light for that but it's been ages (not since my 63 Beetle) since I've used a timing light.

Zero

to check the timing you point the timing light into the access hole on the trans.. right by the engine code stamp.. point it in there.. im not sure how to check it as ive never checked it on mine before.. but im sure someone here would help out more then i can :cool:

but to check the sensor.. is your PGM-FI light on in the dash? if so check the code it threw by looking under the driver seat behind it.. you will see a little window on the ecu and a red led flashing if it does have a code

[ZeroLux]

but to check the sensor.. is your PGM-FI light on in the dash? if so check the code it threw by looking under the driver seat behind it.. you will see a little window on the ecu and a red led flashing if it does have a code

Which sensor are you referring to? The TW sensor that is giving me the problem? It's not triggering a code, no CEL, hence the difficulty in pinpointing it. I think the fact that it's causing some resistance at all is why it hasn't flagged a problem yet. The system runs on a 5v rail and checks the return for the voltage drop in the computer then adjusts the fuel trim based on that. If it's giving 0 resistance it runs wide open thinking the engine is cold, the operating temp resistance is between 200 and 400 ohms, and the one I have right now is giving about 150 ohms at all times, so it's between the range of cold and not-quite-warm-yet and I am assuming the car does not have an internal timer like some do that causes a code if the car does not reach operating temperature within a given amount of time. (The Dodge was notorious for this) I can't even imagine what would happen if someone were to put a higher resistance load on that plug, like a 1k resistor or something. If it even allows for it the system would go massively lean and likely not even run. I've checked the ECM several times but there are no codes.

My next step after I replace the sensor on Thursday is to take a closer look at the EGR valve and see if it's fouled up, same with the O2 sensors I just installed last month since I am sure they are toast now. Good thing they are under warranty I can get a couple new ones pretty easy.

When I went to NAPA this morning they said there's a temp sensor located in the block of the engine. Now, considering where mine are located on the LX-i setup here I think it's open to debate as to where exactly they are at. I personally would say they are located on/in the intake manifold. Is there another sensor that I have not seen yet that is located in another place that I should take a look at while I'm in there? There is also a smallish looking sensor on the passenger side of where the other two temp sensors are, best I can tell is it has a single green wire coming out of it and is very slender in diameter and about 2 - 2 1/2 inches long. Any ideas on what that is? I have not traced the wire yet.

I took a few pictures yesterday, I can post those if needed.

Zero

[1987AccordLx-i]

Which sensor are you referring to? The TW sensor that is giving me the problem? It's not triggering a code, no CEL, hence the difficulty in pinpointing it. I think the fact that it's causing some resistance at all is why it hasn't flagged a problem yet. The system runs on a 5v rail and checks the return for the voltage drop in the computer then adjusts the fuel trim based on that. If it's giving 0 resistance it runs wide open thinking the engine is cold, the operating temp resistance is between 200 and 400 ohms, and the one I have right now is giving about 150 ohms at all times, so it's between the range of cold and not-quite-warm-yet and I am assuming the car does not have an internal timer like some do that causes a code if the car does not reach operating temperature within a given amount of time. (The Dodge was notorious for this) I can't even imagine what would happen if someone were to put a higher resistance load on that plug, like a 1k resistor or something. If it even allows for it the system would go massively lean and likely not even run. I've checked the ECM several times but there are no codes.

My next step after I replace the sensor on Thursday is to take a closer look at the EGR valve and see if it's fouled up, same with the O2 sensors I just installed last month since I am sure they are toast now. Good thing they are under warranty I can get a couple new ones pretty easy.

When I went to NAPA this morning they said there's a temp sensor located in the block of the engine. Now, considering where mine are located on the LX-i setup here I think it's open to debate as to where exactly they are at. I personally would say they are located on/in the intake manifold. Is there another sensor that I have not seen yet that is located in another place that I should take a look at while I'm in there? There is also a smallish looking sensor on the passenger side of where the other two temp sensors are, best I can tell is it has a single green wire coming out of it and is very slender in diameter and about 2 - 2 1/2 inches long. Any ideas on what that is? I have not traced the wire yet.

I took a few pictures yesterday, I can post those if needed.

Zero

first off.. the pics would help.. and to what napa said.. i dont have a coolant sensor on my block.. but yet i have an 87 lxi.. it might be different from yours.. but if the tw sensor is bad.. might as well replace it.. :dunno:

[ZeroLux]

Here we go.

First shot is of that mystery sensor I've not traced yet. Oh and I was wrong, wire appears to be yellow in this shot. It's directly to the left of the green plugged temp sensor, pointing left, just above the distributor, right beside (in the photo) the intake mani end of the EGR pipe.

http://farm4.static.flickr.com/3043/3112127976_f5d7ac7e82_b.jpg

Second shot, just the overall engine at the moment.

http://farm4.static.flickr.com/3088/3111290161_96db2f502b_b.jpg

A little dirty but otherwise not too bad imho. Driver's side injectors leak at the O rings a bit but I'll get around to fixing that sometime.

Zero

[1987AccordLx-i]

oh that mystery sensor is just your temperature sensor ^_^ it simply sends the signal to the dash temp gauge

but the engine looks to be in great shape..

i noticed you have a sensor unplugged on the thermostat housing.. is that the tw sensor? im not too familiar with that one but the green one is the ECT sensor im familiar with that one.. thats the one that messes up the idle if its bad

[ZeroLux]

i noticed you have a sensor unplugged on the thermostat housing.. is that the tw sensor? im not too familiar with that one but the green one is the ECT sensor im familiar with that one.. thats the one that messes up the idle if its bad

o.O wait... WHAT? Beside that green one (which I thought controlled the fans) is the beige one (the one that's unplugged, which I was lead to believe is the one that dictates the fuel mix). Yes, that photo has the one disconnected and jumped with the 330ohm resistor. So the little skinny one is the one that gives the dash gauge temp?

Zero

EDIT: I might have mis-read what you posted. Yes, I have the one disconnected. It's hard to see but it's wedged between two rubber lines to keep it from touching anything too hot. The resistor is underneath the black electrical tape to hold it in (directly below "15" on that upper hose). So I have three sensors, eh? Charming. Just more stuff to replace.

[1987AccordLx-i]

o.O wait... WHAT? Beside that green one (which I thought controlled the fans) is the beige one (the one that's unplugged, which I was lead to believe is the one that dictates the fuel mix). Yes, that photo has the one disconnected and jumped with the 330ohm resistor. So the little skinny one is the one that gives the dash gauge temp?

Zero

oh snap.. my mistake man.. i forgot about that sensor.. why is it unplugged?

but the green one above the #15 hose is the Engine Coolant Temp sensor.. thats the one that messes up idle and makes it run rich.. but if you dont have a code thrown.. it cant be it.. if it is the ECT then the comp would throw code 6.. but above the green one is the temp gauge sending unit.. the long one..

[ZeroLux]

oh snap.. my mistake man.. i forgot about that sensor.. why is it unplugged?

but the green one above the #15 hose is the Engine Coolant Temp sensor.. thats the one that messes up idle and makes it run rich.. but if you dont have a code thrown.. it cant be it.. if it is the ECT then the comp would throw code 6.. but above the green one is the temp gauge sending unit.. the long one..

Ok so now I'm totally confused. I thought the one that is unplugged was the one that is having the problem, hence the unpluggedness of it. So the green one might also be an issue?

Zero

[ZeroLux]

Ok let's simplify because I think I am getting lost in terminology and acronyms here.

http://farm4.static.flickr.com/3109/3111428831_26eb33cd1f_o.jpg

Highlighted in GREEN: I was told/thought controlled the fans
Highlighted in RED: Goes to the dash temp gauge unit?
Highlighted in ORANGE: I thought was the "TW" sensor that was causing the rich condition. Am I wrong with this?

If so then I am totally confused since jumping the one in Orange seems to have made a change for the better. Maybe I should try the same with the green, eh?

Zero

[1987AccordLx-i]

Ok so now I'm totally confused. I thought the one that is unplugged was the one that is having the problem, hence the unpluggedness of it. So the green one might also be an issue?

Zero


EDIT:
Highlighted in GREEN: Thats the ECT sensor
Highlighted in RED: is the temp sensor.. goes to the dash
Highlighted in ORANGE: that one controls the fans

when you jumped the orange one.. did the fans go on?

[ZeroLux]

Highlighted in GREEN: Thats the ECT sensor
Highlighted in RED: is the temp sensor.. goes to the dash
Highlighted in ORANGE: that one controls the fans

when you jumped the orange one.. did the fans go on?

That is a tricky question, my passenger side fan at some point in it's life was tampered with and runs full time if the key is in the ACC position in the ignition. The other one I am not sure, it might have changed, I was in the car and not listening for it after I did the jump. So the GREEN one is the one that runs me rich? Guess I should ohm test that one now. Back to square one I guess. I'm glad you corrected me on it now though before I spent money on a sensor I didn't need.

Zero

[1987AccordLx-i]

That is a tricky question, my passenger side fan at some point in it's life was tampered with and runs full time if the key is in the ACC position in the ignition. The other one I am not sure, it might have changed, I was in the car and not listening for it after I did the jump. So the GREEN one is the one that runs me rich? Guess I should ohm test that one now. Back to square one I guess. I'm glad you corrected me on it now though before I spent money on a sensor I didn't need.

Zero

no problem man.. i even went out to my car to double check it.. unplugged the green one and sure enough it threw code 6 ECT sensor.. but be warned.. make sure its that because the ECT is pretty pricey.. if you lived close enough to me id give you mine cheap.. for i just bought it (my cars not running btw)

but plug that other one in.. if your car was over heating then theres your answer to that.. but you said its on continuously so idk what happened there

[ZeroLux]

Thanks. At this point I am going to spend my day tomorrow poking and prodding under the hood to see what gives. My next option, the one I've been avoiding simply on principle is to take it to a local Honda specialty shop. They charge a flat $42.50 diagnostic fee to find all the problems with the motor, then if you elect to have them fix it they can apply that fee towards repairs. I am not big on mechanics for many reasons, and I learned a long time ago that if you can fix three simple things in life you save a ton of money: Cars, Computers, and Houses. Luckily I am a computer engineer, I know enough about cars to be dangerous, and houses aren't too hard either. I like being a Do-It-Yourself'er, better sense of pride when things go right. Plus I'm a thrifty bastard :) Oh, and I'm out in the Raleigh, NC area.

Oh, and the car never overheated btw. At least not since I've owned it. So now I am more curious than ever wtf that plug I've been messing with does.

Zero

[1987AccordLx-i]

Thanks. At this point I am going to spend my day tomorrow poking and prodding under the hood to see what gives. My next option, the one I've been avoiding simply on principle is to take it to a local Honda specialty shop. They charge a flat $42.50 diagnostic fee to find all the problems with the motor, then if you elect to have them fix it they can apply that fee towards repairs. I am not big on mechanics for many reasons, and I learned a long time ago that if you can fix three simple things in life you save a ton of money: Cars, Computers, and Houses. Luckily I am a computer engineer, I know enough about cars to be dangerous, and houses aren't too hard either. I like being a Do-It-Yourself'er, better sense of pride when things go right. Plus I'm a thrifty bastard :) Oh, and I'm out in the Raleigh, NC area.

Oh, and the car never overheated btw. At least not since I've owned it. So now I am more curious than ever wtf that plug I've been messing with does.

Zero

yeah i dont like mechanics neither.. they try to cheat you for more money.. but really check that ect sensor.. id rather pay for the part rather then have some guy who dont know what hes doing tell me something he dont know is wrong haha.. but that sensor you disconnected im pretty sure is the fan switch.. though i could be wrong

dang im over in california.. if you were in the area id help a fellow 3g owner out but your just too far. and i dont have a paypal thingy.. or however parts are exchanged on this

[ZeroLux]

dang im over in california.. if you were in the area id help a fellow 3g owner out but your just too far. and i dont have a paypal thingy.. or however parts are exchanged on this

That's cool I appreciate the offer though. So the sensor I need to be looking at IS the green one, correct? I'm half considering going out there now and tinkering with it just to see what happens. I might have read the FSM wrong, it's not very clear at some points. I never did read the section about the cooling system but I took a look at it a few minutes ago and it makes a little more sense now. Damn them for having three almost identical sensors right beside each other. I wonder wtf I did now. Hmmp. Oh well, car is still alive.

Zero

[ZeroLux]

Wait a sec. Here we go. I think I did have it right...

http://img353.imageshack.us/img353/5672/thermalzb4.jpg

That's a page from the FSM I downloaded. TW Sensor is beige (the one I jumped), Thermo SW is green, and Thermo Unit is the skinny one.

Zero

[1987AccordLx-i]

Wait a sec. Here we go. I think I did have it right...

http://img353.imageshack.us/img353/5672/thermalzb4.jpg

That's a page from the FSM I downloaded. TW Sensor is beige (the one I jumped), Thermo SW is green, and Thermo Unit is the skinny one.

Zero

the green one should be looked at.. but the other supposed fan switch.. thats what i was told it was for.. correct me if im wrong

[Demon1024]

Wait a sec. Here we go. I think I did have it right...

http://img353.imageshack.us/img353/5672/thermalzb4.jpg

That's a page from the FSM I downloaded. TW Sensor is beige (the one I jumped), Thermo SW is green, and Thermo Unit is the skinny one.

Zero
2x yep..... i thought so too
got me wondering if you could swap the sensors from one hole to another. never took the thermo one out when i swapped my tw

[ZeroLux]

got me wondering if you could swap the sensors from one hole to another. never took the thermo one out when i swapped my tw

I was wondering this too. The connectors look the same. I know the bolt sizes and the sensor shaft sizes are different since I've seen both removed. The green one has a large sensor and the beige one has a very small sensor. Since one of my fans runs constant I think swapping them for a test run can't hurt too much. *picks up keys and walks towards door*

Thanks again!

Zero

[1987AccordLx-i]

glad to be of some help.. keep us posted!

[Demon1024]

No!
just the sensors from one hole in the case to the other.
o well too late now i suppose
i guess it wont mess anything up,but i don't play with connections after blowing my first ecu.
when did that pic get there? i didn't know i quoted a pic!

[2oodoor]

you said again that the engine wont even rev for you, that really sounds like fuel delivery to me, nothing in engine managment would make it totally not pull up eventually.
Some times depending on your year, the dist advance mechanism can freeze up not letting it advance fully but it still would rev up eventually.
You can set the timing by lookng at the slot on the dist hold down bolts... mark where it is then loosen it and move it till the idle rpm go up a little the lock it down for a test drive. Make sure there is no pinging or spark knock or hard starting. Siince you marked the spot it was at if you dont like it you can put it right back. You will run across one of these cars with the timing belt a tooth or so off and the dist was either never moved to check after the belt install or it was moved to compensate for a bungled belt job.
I guess you checked the fuel regulator, but heh anyway that would be giving you idle problems at some point, you have no idle problems which is totaly out of the ordinary too heh heh. There is where you look at engine mananagment ecu crap.. 2 mo cent

[ZeroLux]

I have idle problems, just have not found the source yet. And no, I didn't go playing with plugs last night, picked up my keys and got distracted by a shiny thing and never made it to the door. Stupid shiny things :/ Anyway, timing was going to be my next system to look at. Let me rephrase for the record- I CAN rev her as high as I want, I can redline it easy... just not while in gear. A variety of results would happen if I do that. Power surge for all of a split second, valves rattling like hell, kickdown cable going nuts- just something. It never lasts long enough to figure out wtf she did wrong. There is plenty of power to be had from the feel of it there's just something holding her back.

I can peg high revs all day long in N or P engine sounds like a champ and crap I just thoughta somethin :/

Saaayyyyy.. how hard is it to replace trans of these thing? :) I want a manual anyway.

Zero

EDIT: One last thing, let's say it might be timing. I don't have the resources available to me at the moment to pull the belt section apart and I don't own a timing gun, would it be a bad idea to adjust the dist and turn it back towards the firewall a bit to advance it in it's current unknown condition, or would that cause more problems?

[2oodoor]

OH crap, that sounds like mine when I had the TV cable way out of range. It could be your cable, something isnt right.. and what do you mean your kickdown thingy is going nuts?
That sounds like it is trying to drive in first and fourth at the same time, or the torque converter is fubar. Try a head to toe inspection of that cable, and make sure the housing isnt attached to anything under the hood it shouldnt be. We are a long way from fuel problems now. LOL. shiny things

[Dr_Snooz]

My money is still on an exhaust restriction. I owned a '76 Accord years ago. It had 198,000 miles when I bought it and 250,000 when I gave it away. It was a beast and I was always fixing something. One of the problems I had was no power on the highway. I could give the thing all the gas in the world and could not coax it any faster than 55. I had no idea what was wrong so I took it to the dealer for diagnosis. There happened to be an old fart there who worked on the old Accords back in the day. He told me I had an exhaust restriction. With the advanced age and mileage of the car, the baffling inside the exhaust manifold would break apart and plug the exhaust pipe. I pulled the manifold and sure enough, there was a big obstruction. The car run fine around town and had plenty power in the driveway. It was just at highway speed that the problem manifested.

The point is, these cars are old. Really, really old and well beyond the service life to which Honda engineered them. Expect them to break in creative ways. The ECT sensor isn't your problem for three reasons. One, it would flash a CEL. Two, your jumpering would have fixed the problem. Three, if the ECT was wildly out of spec (yours isn't) the ECU would revert to a default factory fuel map preventing the egregious symptoms you have.

It's not the TV cable or the TC because you'd have problems all the time and not just at highway speed.

It could be timing, but I doubt it. Advanced timing would cause pinging, so that's not you. Retarded timing can cause poor mileage and hesitation at speed. That sounds like you, but I don't think our distributors allow you to retard far enough to cause the symptoms you are experiencing.

There's no shame in taking the car to someone else to have it diagnosed, and the money spent often ends up being more than worth it. I recommend you take the car to a dealer and ask them to diagnose it properly. DO NOT take it to the fix-it shop. What they have in mind is a safety check. They will charge you $42.50 and tell you that you need a turn signal bulb and new wiper blades. That's not what you need. If you go to the dealer, especially a reputable one that's been around a long time, you are more likely to have an experienced old fart like I did who knows the car inside and out. If you find one, take him a six pack and make a friend.

Good luck!

[ZeroLux]

Well like I said, the car has multiple problems. Right now I am focusing on the one that is draining my fuel tank within a little over 200 miles :/ Yes I have a high idle problem, and after the car is warmed up a bouncing idle problem. Sometimes that quiets down and does not happen but that is rare. It fluxes between 1200 and 1800 rpm's when not in gear most of the time. I have a few ideas on that just have not looked into it much yet.

Yes, the TV cable is pooched most likely. Out of adjustment would be my guess. Have not had the chance to look at that yet. It ONLY effects things when in fourth, I feel an occasionally bump (not a hard one) down to 3rd (or so it seems), rpm's dont change, it simply lets go of 4th and goes to 3rd then back up to 4th again. All while maintaining a constant speed (or trying to). That seems more like vacuum to me but I could be wrong.

Yes I agree too, it feels sometimes like an exhaust restriction. Where or why though I don't know either. I can't say either way right now about the condition of the TW sensor as when I jumped it with the resistor the car appeared to drive much better. Not 100% but it certainly gained it's power back and didn't leech all my gas.

This car is getting more than irritating. The local shop I know of is a Honda specialty shop and has been around for 30+ years here in town. I figure I can get them to diagnose most of it and I can fix things from there. If it's something beyond my reach I'll get them to fix it. No shame in it, I just really hate wasting money on something like that. Going to a dealership around here is virtually out of the question. Local dealers have a reputation of either A> telling me to piss off and buy another car (preferably theirs) or B> not even being able to work on certain cars anymore due to age and even if they can, they would more than likely charge me out the ass to tell me the car isn't worth anything.

Zero