NO idle when cold, can't figure this one out.

[Huntervf]

Ok, on my new 95 ATX the car will not idle at all when cold. Turn the key, the car fires right up but then just dies right back out. When warm the car seems to idle ok, but I still think it's a bit low (600-800 RPMs). Here's what I've done so far to troubleshoot the problem:

-Pulled codes when cold (had to help the car run until the KOER test took over, then the idle stayed around 500-600 for the whole test.) Only codes received were 411 & 412...idle speed too high & idle speed too low. KOEO codes gave me a 543 when cold but I could hear the fuel pump running just fine. KOEO when warm gets 111, as does KOER. Memory only has O2 codes; the front O2 is changed and the rear will be done shortly.

-Cleaned IAB
-Replaced IAB
-Cleaned TB
-Cleaned EGR
-Swapped TPS with a known good TPS
-Swapped MAF with a known good MAF
-Replaced front O2 sensor
-Tried to reset the idle, car still won't run

The car runs and drives fine. No noticeable loss in performance, no misses, no hiccups. When warm I still believe it idles a bit low, though I may just be used to my 89 that's chipped. Idling in gear the car usually indicates 700-800 RPM, sometimes it's a bit lower, like maybe 600.

I have noticed that the engine sits noticeably lower in the front as compared to another 95 ATX...it's lower in the front by a good 2-3 inches. I'm assuming a bad motor mount causes this (and it's defintely bad) but you don't suppose the engine sitting forward is putting a kink on something somewhere??

I haven't found any obvious vaccum leaks, and I don't hear anything out of the ordinary from the engine bay.

One final thought: When I first picked up the car I couldn't get the KOER test to run properly...I'd get up to the goose test but afterwards no CE flashes at all. I thought there may have been a computer prob but everything else seemed ok and the last two times I've attempted a KOER everything has been fine shrug

I'm pretty damn lost at this point. I'm ready to head for the shop, toss them money and say "fix it." Any thoughts/opinions on this would be helpful! thumb

 

[sdpatt]

Reset the idle speed program.

 

[DougLee25]

I know you said you did reset the idle program, but did you make sure you had on all the accessories when you did it? You could also try another computer from a known working car and see if that helps since you stated that it wouldn't run the KOER before.

Doug

 

[projectSHO89]

Sounds like the IAB bypass passages are clogged or the IAB is not working.

If the valve is KNOWN to be good (there's only one way to KNOW it's good), then focus efforts on it's control circuit and wiring connections.

The RED wire at the IAB should have VPWR (Batt voltage) on it with the ignition on. The Orange/Black wire receives a variable duty cycle signal from the PCM pin 21. Check those and see what you get.

Test your motor mounts per the FAQ procedure. If the front mount has collapsed that far, there's a possibility that the wiring harness is under strain and causing faults.

Steve

<small>[ April 16, 2003, 08:57 AM: Message edited by: projectSHO89 ]</small>

 

[Huntervf]

I tried to reset the idle speed program to no avail, it won't stay running without input from the gas pedal. I cleaned the **** out of the IAB then replaced it with a brand new one shrug

I'll do some investigating with a voltmeter tonight & see what happens.

<small>[ April 16, 2003, 09:19 AM: Message edited by: Huntervf ]</small>

 

[projectSHO89]

I didn't mean the IAB itself, I meant the air passages in the intake and throttle body through which the IAB air must pass.

Check for a damaged IAB gasket, while you're at it.

Steve

 

[F-22 Raptor SHO]

As to the IAC passage, I meant to ask someone about the significance of cleaning the intake passages during a 60k. When I did mine, I saw that there appeared to be some sort of sample tube inside the intake about where the IAC hook up. It looked like a hole between the front and rear passages. I had some gunk in mine so i used berrymans and a pipe cleaner to get it nice and clear. It wasnt totally plugged up or anything, but it did have alot of #$%# in it. Could this be what Project SHO is referring to?

Chris and I have been banging our heads over this as it is a great car, just has some problems. As to the motor position, guys this thing looks like it is like 2 or 3 inches more towards the front of the car than mine is. I can only fit two fingers between the Front intake and the plastic cover over the PCM that has the belt configuration and other info on it. Ever aspect of the motor is closer to the front of the car by at least an inch. The alternator is closer to the radiator cap, the wires are really close to the fan. Now mind you, I saw that the mount was broken when we went to go buy the car, I mean its really broke, but would it affect the running condition of the car? Everything else electrical seems ok.

Another note: I told hunter not to touch the gas at all during startup, and I just opened the throttle by hand about 2 or 3 mm and it started and ran just fine. A few turns of that screw would fix this. Trouble is, and we havent verified this, that once the car is totally warm, how would the idle speed be then? 1200? Something else is wrong, I'm sure, but I did note that there is locktight on the screw and it looks like it was never turned, so this would be a jerryrigged fix at best.

Chris, I still think you should take the intake off and clean the **** out of everything when we do my 60k on the 17th. Wont cost you anything but the berryman's. You can reuse alot of your gaskets, or have my lightly used gaskets from mine. It probably isnt the case, but cant hurt to try.

 

[projectSHO89]

Turn the screw and find out. It won't hurt anything and you can always turn it back later.

Yes, that was the tube I was referring to. If it is plugged, there will be no air bypassing the throttle plate. Cracking the throttle slightly allows some air past the plate.

As far as the motor position, make sure that you are not comparing it to an MTX as the positions are different.

Steve

 

[F-22 Raptor SHO]

As far as the motor position, make sure that you are not comparing it to an MTX as the positions are different.

Ya, thats the problem, they are both ATX's and the motor is way forward in Chris's car. I mean waaayyyyy forward. Chris will take a pic of the two of them.