[:@]

Ok, I think this is probably the 4th or 5th time I have been on here. My 94 z28 is STILL running like crap when it heats up. For say you drive it until the temp gets to 190 or so and then shut it off for about 30 minutes and go back out to restart it. As soon as you try and give it gas it sputters, backfires and just basically rattles the whole car. This is the 4th time I've had it in the shop. I've had the whole distributor replaced, cap rotar, and some other minor parts. Today I will be getting my car back cause its been in the shop for the past 3 days. My last post I took Petes advice and printed out everything that he suggested to get checked, About all of my Sensors and that kind of stuff.

I talked to my mechanic today and he said it wasnt the sensors they were all ok. He even checked the fuel pressure, Thats a little low but that would be whats causing it to act like this. Sooooo... He's changing the spark plugs and wires again today to see if that changes anything at all because they were pretty new before.

I just feel that I am at a lost cause here. I've spent over almost $2,000 in trying to guess what could be wrong. Everyone on here whos seemed to have the same problem said that changing the distributor fixed it. Not for me it hasnt.

I guess I am just looking for anymore suggestions or any more ideas. I'm getting to the point where I am tired of guessing at this.

And Pete thanks for the advice you gave me about the sensors last time.

Does anyone have anymore ideas for me? I'm thinking its something really serious this time. If none of these ideas have helped.

I will know in a few hours or so if the spark plugs and wires have helped at all.

I guess I just am really frustrated with my camaro. Nothing seems to be helping the situation at all.

Alright well thanks for any ideas!!!

 

I don't remember the whole story, but have you tried driving around with the MAF disconnected & see if the car still acts up when warm? It will throw a MAF code but you can just ignore it for the time being.

 

This might sound stupid but whats the MAF? I'm not sure what that really is. Like I said my Mechanic does all the work. I'm not that big into car parts like that. Thanks for your help though.

 

is that the Mass Air Flow Sensor? what does this exactly do?

 

The purpose of the MAF (in this application) is to do a final touch up on the air fuel mixture. The bulk of the work is done by the MAP sensor. By pulling the plug on the MAF, causes the computer to go into open loop mode and ignore most sensors except for the MAP and TPS sensors. If the car runs OK in this condition it indicates that fuel and ignition are OK, and that there is a sensor problem.

The Mass Air Flow Sensor locates on the intake plumbing between the throttle valve and the air filter. Just unplug the wires going to it.

This site has a picture of it

http://shbox.com/1/maf.jpg

 

I dont know how to say it Pete....

Thanks for all of your ideas and help with everything.

Although.....I'm sad to say

That wasn't exactly my problem....so I'm back to the drawing board. still running badly when the engines warm. It has to be ice cold to run like it supposed too.


Hmmm.....

 

i had a car that did the same thing. it wasn't a camaro tho. it was a mercedes. nevertheless i went through the exact same symptoms. changed everything you can think of. it only acted up after it was warm. in the end it turned out to be a glitch in the computer itself. replaced the computer and it ran fine until i sold it. not saying that this is your problem but, just telling you my expierence. sick

 

Yeah, I totally am starting to hate this. It only does it when its warm and usually when I'm the only one in the car at that moment.

Is actually weird though because if it starts acting up I can pull over in a parking lot or on the side of the road and rev it up 3 or 4 times and sometimes that clears it, or if I jump on it up to like 5000 rpms. (80% of the time that works).

I just cant even begin to think where else or what else could be causing my problem!!!! [:@]

 

I'm having a similar problem on my '95 Z28. Have you found a source of your problem?

My car runs fine until it gets to about the first quarter mark on the temp gauge - 185°, which is the thermostat temp. Once it gets to this temp, the motor becomes very choppy at low RPM. For instance, on the freeway, if I go to accelerate in sixth gear to pass somebody, it's very choppy and not quite so powerful. Once the RPMs get up to about 2500, there's a noticeable kick in the rear and performance returns.

I started noticing the problem July of 2005. Soon after, I found a hole in my radiator (not sure how long it had been there though). I replaced the radiator and a couple weeks later replaced my heater core after finding DexCool all over my passenger floor board.

I also reverted to the stock thermostat, with no change in performance.

I don't suppose water pumps would affect performance in such a way, would they?

 

I'm having the same problem. It seems to me after reaing through several posts and situations that the pcm seems to always be the culprit. Not saying in ur case it is or even in mine but i think that is the next step im going to take after i try what pete suggested with unplugging the MAF sensor.