Warm restart issue

[Dr_Snooz]

I'm experiencing a warm restart issue. It's not the classic main relay issue where the car won't start when the cabin gets warm. This one happens when the engine is warm. If I try to restart the car within 20 minutes or so of turning it off, it turns over, but won't fire. If I wait, it starts again no problem. My main relay is not a year old at this point, so I don't think it's that. I did notice that the car smelled like fresh gas when it acted up the other night. That has me thinking about injectors. Two of my injectors are original parts. Two others are junkyard replacements. My suspicion is that they are leaking fuel into the combustion chamber after I turn the car off. Wait long enough and the fuel drips into the crankcase and the car starts again. Having said that, the car absolutely does not fire at all when this is happening. It just spins. If there were a lot of gas in the chamber, I'd expect it to cough and sputter some.

I haven't had a chance to do any kind of diagnosis. Just wondering if anyone has any ideas.

[conozo]

Loose plug wire to coil.

That's a complete guess.

[Shane86]

Tw switch

[Dr_Snooz]

Tw switch

Dang. That didn't even occur to me. Good catch.

It's a funny thing about human nature that after a 12 hour workday, you'd rather sit on your butt and watch TV than chase an intermittent car issue while being devoured by mosquitoes. Who knew? Anyway, the car left me sit for over an hour at a gas station last night. I had to call my neighbor to come pick me up. How embarrassing. Tonight I forced myself to go out and test it while it was still warm. The spark was almost not visible and I found the coil to be out of spec with values that kept moving around. This is an 8 year old coil with 25k miles on it. Not very impressive. Wish I had noted down where I got it from. Anyway, I have a replacement coming that I'll install tomorrow night and we'll see what happens.

[InAccordance]

You can have my old one when I'm done with my conversion =D

[Oldblueaccord]

Dang. That didn't even occur to me. Good catch.

It's a funny thing about human nature that after a 12 hour workday, you'd rather sit on your butt and watch TV than chase an intermittent car issue while being devoured by mosquitoes. Who knew? Anyway, the car left me sit for over an hour at a gas station last night. I had to call my neighbor to come pick me up. How embarrassing. Tonight I forced myself to go out and test it while it was still warm. The spark was almost not visible and I found the coil to be out of spec with values that kept moving around. This is an 8 year old coil with 25k miles on it. Not very impressive. Wish I had noted down where I got it from. Anyway, I have a replacement coming that I'll install tomorrow night and we'll see what happens.

I just took another job that 8 hours shifts and my wifes already noticed I have done more around the house in 3 weeks than in the last 6 months.

Ill go with TW sensor. There is some kinda paper clip trick that will jump it out. You can search for that.

Check the specs of the new coil Im gonna guess there not to the book but for the Prelude.

[Dr_Snooz]

Definitely not the coil. So $50 bucks for nothing. I ordered new injectors today. I really think they're leaking down. There's no real way to test that, so I'm considering it a maintenance item.

Wouldn't the TW sensor flash a CEL? I guess when your ECU is 30 years old, there's all kinds of stuff it might not be doing anymore. I've already thrown 2 out for being messed up. It's easy enough to test, so I'll put that on the list.

[Oldblueaccord]

Definitely not the coil. So $50 bucks for nothing. I ordered new injectors today. I really think they're leaking down. There's no real way to test that, so I'm considering it a maintenance item.

Wouldn't the TW sensor flash a CEL? I guess when your ECU is 30 years old, there's all kinds of stuff it might not be doing anymore. I've already thrown 2 out for being messed up. It's easy enough to test, so I'll put that on the list.

Im guessing unless it read 0 it wont code out.

Reading warmer than it should will make the car way rich. When my t stat stuck all those years ago my AFR was 10:1 just idling and pegged down at 9 driving a short distance at part throttle.

Starting at full throttle may clear out excessive fuel on our cars. my new OBD2 cars wont start if you full throttle them,no fuel. I use it to prime the oil pump of oil changes a few seconds before firing off.

[Shane86]

Definitely not the coil. So $50 bucks for nothing. I ordered new injectors today. I really think they're leaking down. There's no real way to test that, so I'm considering it a maintenance item.

Wouldn't the TW sensor flash a CEL? I guess when your ECU is 30 years old, there's all kinds of stuff it might not be doing anymore. I've already thrown 2 out for being messed up. It's easy enough to test, so I'll put that on the list.

First when my TW switch went out it never threw a code. i threw all kinds of money at it trying to fix it. Then about a month later I noticed the plastic was cracked and I decided to go ahead and replace it. But the car was having all the kinds of symptoms as you described

[conozo]

https://www.3geez.com/forum/efi-tech...ification.html

Here is a great thread on the TW sensor. I found that Rock Auto has one but list it as DX,LX,carb one. Is there really a difference?

[Dr_Snooz]

I tested the sensor and couldn't really get a good connection, so I replaced it. Problem remains. I got my injectors in the mail, so those are next up. Stay tuned for more fun!

[Dr_Snooz]

I might be wrong. It started right up twice today. My first warm start with the new sensor failed, but maybe it's been driven enough now to re-write the map. I need to drive it some more.

[Dr_Snooz]

Okay, no, definitely NOT the TW sensor and DEFINITELY the injectors. I got a couple sputtery restarts after replacing the TW sensor, but the problem returned full force after that, leaving me sitting in Whole Foods' parking lot with my hood up for a half hour. I got it home and pulled the injectors, which were dribbling gas even as I removed them. I've only restarted twice since then, but the problem appears to have been eliminated.

It's funny how you come to know your car. When it all started, I smelled the gas and said, "I'll bet it's those injectors." I tried restarting with the gas pedal pressed to the floor, which seemed to help, so that kind of confirmed it. I'm always careful to do as much testing and troubleshooting before I start spending, so I did a couple other things first, but those injectors kept coming to mind throughout.

All that to say, keep turning those wrenches!!!

[Dr_Snooz]

As long as I'm on the topic of fuel system service, WTF is with Honda's screwball fuel filter banjo bolt? It aims itself at the fuel line so you can't get a wrench on it. Real nice. It's some stupid two-sided bolt that you have to use an open end wrench on (not a socket like you'd like to use). Has anyone replaced that nonsense with a proper hex-head banjo bolt? That's on my list of stuff to re-engineer now.

[InAccordance]

Go get you some red top DSM injectors, can squeeze a bit more flow out of them. From what I remember it isn't much but is a little more than our stock ones.
I also found old GM ones that worked too. Those were fun.

[Shane86]

As long as I'm on the topic of fuel system service, WTF is with Honda's screwball fuel filter banjo bolt? It aims itself at the fuel line so you can't get a wrench on it. Real nice. It's some stupid two-sided bolt that you have to use an open end wrench on (not a socket like you'd like to use). Has anyone replaced that nonsense with a proper hex-head banjo bolt? That's on my list of stuff to re-engineer now.

You can replace it with this Honda fuel pressure gauge.





https://rover.ebay.com/rover/0/0/0?m...2F112367718711

[Dr_Snooz]

I'm WRONG! Problem persists. Doh.

The car is running SOOOOOOO much better with the new injectors though. OMG. My notchy throttle response is gone. Idle is smoother; running is smoother; power is increased; probably MPG too. I had no idea they were so bad.

I figured out how to start it though. I just put my foot to the floor and keep cranking. Works great. Of course, you know how that goes. Twenty years from now I'll still be starting it that way and still saying, "I really need to fix that." LOL

Does anyone have a good way to test spark when you're alone?

[Dr_Snooz]

You can replace it with this Honda fuel pressure gauge.





https://rover.ebay.com/rover/0/0/0?m...2F112367718711

Thanks!!

[Oldblueaccord]

I'm WRONG! Problem persists. Doh.

The car is running SOOOOOOO much better with the new injectors though. OMG. My notchy throttle response is gone. Idle is smoother; running is smoother; power is increased; probably MPG too. I had no idea they were so bad.

I figured out how to start it though. I just put my foot to the floor and keep cranking. Works great. Of course, you know how that goes. Twenty years from now I'll still be starting it that way and still saying, "I really need to fix that." LOL

Does anyone have a good way to test spark when you're alone?

I use one of those AC tic tracers. Death sticks as there called in my business. I got a fluke one that picks up the pulse thru the wire. or use a timing light.

http://www.testequipmentdepot.com/fl...SABEgL-vPD_BwE


the foot to the floor tells me its flooding some how.

[carotman]

Which sensor did you replace, the 2 prongs one or the single prong?

[Dr_Snooz]

Which sensor did you replace, the 2 prongs one or the single prong?

It was the 2 prong closest to the head.

The car wouldn't start again Thursday night, and I actually had a chance to do some proper diagnosis. Pressing the pedal to the floor did nothing this time. I'm definitely getting fuel, because I can smell it. And I'm definitely getting fire. Sort of... The spark is underwhelming, coming in a 22k volts when it should be closer to 30k if I'm understanding things properly. My coil is new, so I doubt it's that. Nor do I think it's the dizzie because I tested before it too and got the same meager 22k volts. So I'm thinking whatever is wrong is happening before the dizzie. I've noticed that when this happens, the starter doesn't run as strong, like the battery is tired. I've also had a few starts where the entire electrical system is dead when I turn the key. No dash lights, no start, no nothing. If I turn off the key, jiggle it and try again, it starts normally. Thus, I have a new ignition switch coming.

I need to get snuggly with the wiring diagrams today to see what's happening before the coil. I think that fuel pressure gauge above is a good idea too, so I'll order that, just to be sure of what the fuel is doing.

This is the weirdest thing. The car will crank, but not fire. It won't even try to fire. It doesn't cough, sputter, choke or anything. It just spins.

All thoughts and suggestions are appreciated.

[InAccordance]

Take the ignition switch out, pull the white part off, take some sandpaper and clean up the contacts on the black part side. Instant new ignition switch. Just be careful not to let the bits fall out of the white part of the switch (been there done that).
I've had it happen twice where one of the contacts gets a sort of like burnt spot on it and was preventing contact.

[Oldblueaccord]

It was the 2 prong closest to the head.

The car wouldn't start again Thursday night, and I actually had a chance to do some proper diagnosis. Pressing the pedal to the floor did nothing this time. I'm definitely getting fuel, because I can smell it. And I'm definitely getting fire. Sort of... The spark is underwhelming, coming in a 22k volts when it should be closer to 30k if I'm understanding things properly. My coil is new, so I doubt it's that. Nor do I think it's the dizzie because I tested before it too and got the same meager 22k volts. So I'm thinking whatever is wrong is happening before the dizzie. I've noticed that when this happens, the starter doesn't run as strong, like the battery is tired. I've also had a few starts where the entire electrical system is dead when I turn the key. No dash lights, no start, no nothing. If I turn off the key, jiggle it and try again, it starts normally. Thus, I have a new ignition switch coming.

I need to get snuggly with the wiring diagrams today to see what's happening before the coil. I think that fuel pressure gauge above is a good idea too, so I'll order that, just to be sure of what the fuel is doing.

This is the weirdest thing. The car will crank, but not fire. It won't even try to fire. It doesn't cough, sputter, choke or anything. It just spins.

All thoughts and suggestions are appreciated.

if you get low like under 12 volts the car will crank but not fire. I got mine to fire off at 11.5 volts but just as I let the key off it fired. Thats 11.5volts at the battery at rest,cranking voltage could fall to 9 volts.

Long shot I doubt thats your problem.

[charliekuney]

How reluctant is PGM-FI on a correct battery charge? I had a cheap Les Schwab battery in my Lexus and the .2-.3 volts lower it produced versus an OEM Lexus battery caused the car to hesitate (electronic throttle) and go into limp mode.

[Dr_Snooz]

Hey Charlie. Welcome back!