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View Full Version : 1986 LXi miss on 1 & 4



Trent Von
04-09-2019, 05:51 PM
So I did some maintenance on the cooling system and replaced that little 2 inch hose underneath the intake manifold..... that operation was successful, now on to the stressful, LOL!
I've got no power out of 1 & 4. Checked the compression and got about 150 -145 on all 4 cylinders (out of a 360k motor, not great, but not bad.) Also, that dam compression tester was a loaner tool from O'riely's all messed up. I could feel a leak in the hose while cranking, so who knows.... at least I know it's 145 or better.
I've got spark on all 4 cylinders.
I've got 12 volts to each injector on the (+) side, and I have 2 ohms on the injector itself

I plan on doing the injector swap around to see if the dead'ness follows the injector over to #2 or #3

My question to everybody here is, is their something that might be considered a "sensitive zone" around the coolant line work I did? Has anyone ever encounters a similar situation?
Everything was great before I did the work on that hose. I can't imagine that a simple trip up and down the car ramps did anything that wild! Hell, was still getting 31 mpg over the past week.

Any help to my little blue 3'rd gen Accord would be GREATLY appreciated :)

Trent Von
04-10-2019, 08:56 AM
Just use an automotive stethoscope (should'a done in the beginning), all injectors are clicking. The only thing I can guess now is a clogged injector or low fuel pressure.
To review:
> No smoke while engine is running
> I have compression on all 4
> I have spark on all 4
> 2 & 3 have power, 1 & 4 don't..... gotta be fuel

Oldblueaccord
04-10-2019, 05:40 PM
what did you use to decide that no power on 1 and 4.?

there is a ground wire I think its under the fuel injection rail its important to the the injectors firing.

Dr_Snooz
04-10-2019, 06:29 PM
What does the exhaust smell like?

Trent Von
04-11-2019, 12:10 AM
> Oldblueaccord, I simply pulled the wires from the dizzy one at a time to observe any change in RPMs. As I pulled the wires 1 & 4 got no change, 2 & 3 the motor would almost stall out. The other advantage was seeing a blue arch spark as I pull out the wire, so I know energy is finding its way to the plug. Additionally, I changed all the plugs and wires to NKG.
Thanks for the tip on the ground wire, I was fussing around quite a bit trying to get a good angle on the hose underneath the intake manifold, wouldn't surprise me that I knocked that loose.

> Dr_Snooz, Yup the exhaust has a real weird smell to it.

After I get home tomorrow I'm gonna stop by the part store to rent a fuel pressure tester as well a a noid light set just so I know what the health of the fuel delivery system is.

Thanks guys, I really appreciate you taking time to respond to my questions.

Dr_Snooz
04-11-2019, 06:53 PM
Have you checked the rotor and cap? What does the inside of your distributor look like?

Trent Von
04-12-2019, 08:36 AM
Re: Dr_Snooz

Everything on the dizzy looks great, no water, no corrosion.
I went one step further to see if my diagnosis was correct and apparently I was way off.
> I pulled wires 1 & 4, car ran (as I expected)
> I then puled wires 2 & 3 and the car ran on those two as well..... so much for my "missing 1 & 4" theory

Back to square one, still running with a ruff idle.

What I know;
> Compression test returned good data.
> All injectors working well (even shuffled them around)
> Ignition timing good. TDC with no vacuum lines attached to advance, 15 degrees with vacuum lines
> New NKG plugs and wires
> When I pinch the fuel line after the regulator the engine tends to bog down, kind of like I was forcing too much fuel into the system. I'm gonna replace the regulator today (still under warranty), however, that was weird.
> Road test returned mixed results. Acceleration through the power band 2.5k - 4k rpm was smooth, although I noticed a bit more throaty exhaust sound, kind of like it was wanting but couldn't give. As soon as I came to a stop it chug, chug, chug, glugged and stalled out.

Work that was done on this car was that small coolant line underneath the intake manifold (which work great now.) The parts I came in contact with would be around the distributor, EGR valve, the vacuum brain box and whatever feeling around I did to connect those coolant lines.

I was wondering if you had any info on the EGR valve on how to test that part. I know that if that's wonky it could make everything run ruff and rich

Here's a snapshot of my hood sticker
9529

Trent Von
04-12-2019, 04:29 PM
.....additional, I'm not getting a ECU light on the dashboard yet. If I'm right (and please let me know if I am), but the code 12 wouldn't come on unless I put it through a proper drive cycle (I'm guess'n.)
I have the car in the driveway right now and I'm using a dam minivan as my daily (I feel so yuck about that, BTW. I feel like and Elephant going down the road when I use to be a Cheetah)

InAccordance
04-12-2019, 06:04 PM
Which water line did you replace and why?
There are two lines that go to the idle air control valve, one is an intake and one is an out. They should run back into the pipe behind the head. Basically those act as a temp sensor to the IACV which controls your idle speed. If it was clogged up or removed or whatever and you suddenly put it back to where it works again, the valve may be out of adjustment. Take the two screws off the top and using a quarter, turn the thingy inside it up and down, see if your idle changes.

Trent Von
04-12-2019, 07:32 PM
Which water line did you replace and why?
There are two lines that go to the idle air control valve, one is an intake and one is an out. They should run back into the pipe behind the head. Basically those act as a temp sensor to the IACV which controls your idle speed. If it was clogged up or removed or whatever and you suddenly put it back to where it works again, the valve may be out of adjustment. Take the two screws off the top and using a quarter, turn the thingy inside it up and down, see if your idle changes.

Oh yes, very familiar with that hose, I had a go round with that once before.

This hose was leaking so I had to put a new one in. It connects to the main coolant pipe across the back of the engine to a fitting on the intake manifold right by the PCV valve.9530

InAccordance
04-12-2019, 08:32 PM
WHat does the hose you replaced connect to on the other end (not the pipe end).
I haven't messed with an FI car in years since I had the Prelude over 13 years ago, but 90% of the time an idle issue was caused by the IACV being dirty or out of whack. I've fixed many of them with a phillips head screwdriver and a quarter.

You said the powerband was good from 2.5-4k... what happens after 4k and below 2.5?

If everything was fine before this, check the wiring around the area you worked on. I know it sounds dumb but trust me, I've done it. Accidently pulled a connection loose or forgot to hook something back up, etc etc.

Trent Von
04-12-2019, 09:45 PM
The hose connects to the underside of the intake manifold. It's "piped" at that spot to make it to the topside of the manifold right between the throttle body and the valve cover.
As far as the idle, it's just real rough. Once the idle drops after a few minutes of warming up it just chug, chug, chug, then stalls. No bouncy idle.
Maybe I leaned on the EGR... the more I investigate the probability the more the symptoms seem to fit.

Dr_Snooz
04-12-2019, 10:00 PM
Yeah, it's just something I've noticed over the years doing this that most threads of the type "running on 3 cylinders" or "cylinder 2 isn't firing" translate to "the car is running rough."

For your situation, I'd be looking for a broken vacuum line. You may have broken a sensor wire too. That's a difficult hose to replace and it's highly likely there was collateral damage. Good luck.

InAccordance
04-12-2019, 10:20 PM
Someone may have to clarify for me but as far as I remember, there are no water lines at all that go through the intake manifold on the FI models other than the IACV lines. The carb ones do have water lines that go through the intake but I'm pretty sure the FI do not.
If I'm thinking of what you're describing, that is the PCV line.

InAccordance
04-12-2019, 10:34 PM
https://www.ebay.com/itm/86-87-Accord-OEM-air-intake-manifold-fuel-gas-injectors-STOCK-Lx-Lx-i-M-T-/192716986383

Sorry for it being an ebay link, but about the only picture I could find. go to the pic of the manifold bottom, that small hose connected to a metal fitting right next to the large hose, is that the one you're talking about?

Oldblueaccord
04-13-2019, 01:25 AM
I think I would swap the injectors around since you have two cylinders that are firing and see if the problem moves and reverify that the compression check was right on those bad cylinders.

Trent Von
04-13-2019, 07:50 AM
https://www.ebay.com/itm/86-87-Accord-OEM-air-intake-manifold-fuel-gas-injectors-STOCK-Lx-Lx-i-M-T-/192716986383

Sorry for it being an ebay link, but about the only picture I could find. go to the pic of the manifold bottom, that small hose connected to a metal fitting right next to the large hose, is that the one you're talking about?

Yup, that's the one. It looks real innocent there, but trying to get to it is a real chore.
If I was to get into the heads of the design team for Honda I think this was their way to pass this line from the bottom of the manifold to the top without risk of cooking a rubber hose on the manifold (their is another coolant fitting directly above it right next to the PCV valve.)
9531

Trent Von
04-13-2019, 11:30 AM
OK folks, we're REALLY close to solving this.

So, as I started to suspect, the EGR is going wonky..... could be on it's own or by fault of in proper input.

> First thing, started the car then pulled the vacuum line and plugged it. The car's idle instantly leveled. After it warmed up the idle dropped to it's normal 750 rpm. I tried to reconnect and she instantly started to sputter, so I unplugged it again. After a quick drive around the block everything sounded great with a slight hiccup around 2k while accelerating in 2nd gear. Naturally, when I rolled up into the driveway the car got a code 12 (I expected that due to the fact that I had the vacuum hose disconnected from the EGR)

Gonna dive in the EGR stuff a bit deeper....

InAccordance
04-13-2019, 06:43 PM
Make sure you didnt put the wrong vacuum line on the EGR. I did that once and the car ran like what you're describing. In my case it was one of the vacuum lines that goes the distributor lol. Was amusing because it wouldnt idle to save its life but would fucking scream under throttle.

Trent Von
04-14-2019, 04:13 PM
Here it is, the little bastard. It snapped off and just plugged it off when I put it back together. Silly me, I thought that you didn't want vacuum leaks. Apparently this is suppose to suck air from the air cleaner (a kind of vacuum leak), plugging it causes too much vacuum in the EGR system and pulls the valve open prematurely.
All fixed now.... and learned a bunch about the EGR
9532

Dr_Snooz
04-17-2019, 06:46 PM
Nice work!