I just bought my 94 Camaro 3.4L V6 about a month and half ago.. It's been running good til about last week.. Starting the car everything runs good and then about after 10-15 minutes of driving it runs real rough and shakey. It sounds like no oil pressure or mis firing. If i turn the car off for a few hours it will start and run normal again til warms up.. Since this started happening I've changed the oil, oil filter, fuel filter, air filter, and spark plugs. I kinda think maybe o2 sensors are failing.. But Im not to sure.. Any and all thoughts would be greatly appreciated..

 

are you getting a check engine light? sure sounds like a sensor is failing so a scan for trouble codes would be a good idea to see if we could get a hint which sensor it could be. could also be a coil.

 

Yea the check engine light is coming on. I don't have the equipment to do a scan myself. Been trying to find someone who does.

 

call the local dealer and ask how much they charge to scan. you may want to look at using a laptop. sorry gota go.

 

Ok so I failed to mention that I have a powerful sound system installed as well. After installation the car still ran good for about 2 weeks after. Today I was running errands and it started running rough after the 10-15 min. I parked and started the car about 20 min later and was running fine. I decided to just turn off the radio and amp and drove for a total of about another hour after that and never had the problem come up. I decided to get the alternator tested both with the system on and off and only taking about 1 volt. I left there and turned the radio on and within a min it started running rough again. Turned the radio back off and got home 5 min later. I changed gears and in drive and reverse the engine still ran rough and at about 750 rpm, usually runs between 900-1000 rpm, but in neutral and park it sounds fine and idles just right. Gonna remove the subwoofers. And ideas what is causing this. Its not the alternator or battery and I do have a capacitor running between amp and battery.

 

pick up a aldl cable and software and you can see whats going on using a laptop. this is what your looking for, can get the cable for like 50 bucks and use datamaster or TunerCat or moates ALDU1 and CABL1 for like 80 bucks

 

Awesome. However I feel like a moron now. Today I was driving with radio off and it started acting up again.. This weekend I'm gonna get it scanned to figure out the problem.. This may be a stupid question but does it have to be running badly when I get it scanned or does that matter?

 

nope the codes will store in the computer,,, so long as you dont disconnect the battery. unhooking the battery or completely dead battery will clear the codes.

 

As Craby said, it appears to be a bad sensors. Depending on how a sensor fails it may or may not set a code as the OBDI computer in your car knows enough to set a code on a hard failure, but is not smart enough to pick up sensors sending false data. When you have the car scanned look at all the data that the computer is getting from the various sensors and verify that it makes sense. It could also be that an ignition component is failing when it gets hot, so make sure the ignition is in good shape. Coil packs and the ECM are prone to failure as they get old. However, the OBDI PCM is not smart enough to pick up individual cylinder misfires, but will complain in case of gross misfire by flashing the MIL.

 

I greatly appreciate all the help.. I'll post my findings when I get it checked out.. I'm trying to learn.. I know the basics, I mean basics, I really wanna learn how everything works.. So bare with me..