been trying to diagnose a somewhat interminent problem for a while, its mostly just an annoyance on short trips but turns into a nightmare after driving for a while and I have to take a road trip soon!

I have a 92 SE 5 spd and am dealing with erratic idle, stalling on deceleration and stops (unless I rev it up or it sometimes catches itself). The car will usually be fine for a short while after I give it lots of gas. When I accelerate out of an idle fluctuation, the acceleration is jerky jittery and uneven. Sometimes very hard to accelerate, at all speeds (this last symptom clears itself up after a little bit and the acceleration returns ot normal.. for a while).

So far I've changed fuel filter, spark plugs, checked coils, checked througholy for vacuum leaks, cleaned TB, tested alternator and got a new battery, fuel pressure is normal, Front 3 injectors have normal resistance, I was advised that the problem would be more severe and consistent if it was a fuel injector problem so I haven't checked rear 3. The IAC motor seems to be operating fine. I'm not getting any codes whatsoever, and it runs bad cold too sometimes... though the longer I drive the worse it gets, of that I'm sure (but since its bad cold i can rule out O2 sensor, right?). Once I've been driving for like 40 minutes it becomes barely driveable. The acceelration sometimes gets so bad after a whle that it takes me like 10 seconds to cross an intersection.

I've also noticed by time i finish a semi-long drive, what seems to be my timing chain is making a lot of noise, and the engine and exhaust sounds more distressed and the exhaust seems shaky (though its probably just the shaky engine shaking it). Based on what I've checked, anyone got any tips on what to check next? I wish something would just go out completely so I could figure out what it is easier =(

addition: no problem starting after a stall, MAF ruled out, if i shut the car off for a short while once it starts getting terrible it improves (not completely though)

 

you should try unpluggin your MAF to see if it runs better

just remember it wont rev above 2500rpms when unpluged

 

Did you have your coil packs tested for resistance, or did you just look them over for cracks?

On mine, one of my rear ones was bad and it looked better than the used one I bought to replace it. My car was actually hesitating/bucking, but I also had a cracked one in the front and the car would idle rough/have trouble accelerating sometimes before I replaced that.

Something else that comes to mind is Cam Position Sensor (also called Crank Angle Sensor). I have read where they cause all sorts of problems when they go bad. I tried this initially, but it was the rear coil pack.

The only other thing that comes to mind is a bad TPS, but I am sure some of the more knowledgeable VE guys can think of other stuff.

 

ignition module? anything with transistor hates heat so check there.

 

thx for replies, im out of ideas so any new ones are greatly appreciated!

subs1000w: my bad, i forgot to mention that I've also ruled out the MAF already. thanks

Red92MaxSE: had coils tested for resistance. I'll look into Cam Position Sensor, thanks

93max: ill check into ignition module, thanks

i sorta wish something would just break completely so i could tell what it is!

 

well it seems to be getting worse- maybe im getting my wish that something is going out. Today as i pulled out it bucked much more violenntly than the gentle jerking i talked about before, and stalled as soon as i pulled over. Starts up fine, but stalls almost instantly. Revving it keeps it alive, but hardly even any time to depress clutch really. Still no engine light though, ugh!

 

damn its hard w/out a code..did u check ur fuel pump?

 

This sounds just like my problem 3 months ago. I checked all the things you have done. What I found was the idle problem was solved when removed and cleaned and lubed the IAAC unit,mine wasnot moving. Then I spaced the transsitor pack that controls the ignition coils away from its mount with a couple of small lock washers so there is a space betwwen it and the cylinder head.The heat from the head doesnot get to it and end of problem. It seems as the transistor pack ages it gets more sensitive to heat.
It was a cheap fix and has worked like a charm.
Regards Don

 

my car has an erratic idle and stalls sometimes and i think it is my o2 sensor i bought a new one today ill let you kwno fi that stops it when i install it tomarrow oh and it had also made my car loose some performance like it lags a little and stuff....

 

oh snap...im in minnesota too and i got a spare motor (kinda) so if u need part...holla if i had time i could check it out. also ase certified in electrical ^_^. if u want i need help putting in a motor? know anywhere i can rent a engine hoist cheap?

 

Most parts stores rent hoists. also check tool rental places.
of course they only cost like $200
Much cheaper than a scanner

 

ha thats cool. i dunno about the hoist, i saw one for sale in the paper for cheap a few weeks ago but that was a few weeks ago... what motor are you putting into what?

anyway i talked to an old friend and he said im an idiot for not checking out the EGR valve yet, ill do that tomorrow

 

just throwing another less abused VE in the ride, the ranny went out so i gues i might as well change the motor too since i got a bomb *** deal. u need springs? i have sprints that i need to getr rid of

 

93max: nope, dont need em

Today after getting nothing but code 55 since i started having problems I finally got a code 12 after a short test drive. I then went inside to look up the code, then drove around for a little while longer nad the check engine light flickered on a few times. Checked again and am now getting nothing but 55 again. I wonder if it was just a fluke from me doing something wrong with the ECU. anyway my source says code 12 on a 92 means

"The ECU detected an open or shorted circuit. (An abnormally high or low voltage is entered.)".

looking around on google i also get a lot of mentions of the MAF circuit specifically. disconnecting the MAF before didn't seem to help before, but now the problem is worse, less intermittent, and a little different i guess so maybe I have two problems at once so I should probably check out the MAF again. I've read a few differnt things on the code though, has anyone dealt with code 12 before? from what im reading Right now I'm thinking the MAF wiring may be bad or the MAF itself, i sure hope so so i can replace it. ill have to play with it tomorrow

 

when/where did u check fuel pressure? cuz we had a van come in andfound out the fuel pump was not pumping enough fuel. it would run rough/stall after it warmed up

 

is the pump in the tank or ?

 

yes