Okay, I have a 1991 Firebird with a 3.1 v6 and auto trans. It has been ran for a while with a broken thermostat but almost never overheats due to the current cold weather. Also it is almost time for an oil change but uses synthetic oil so should be able to go for a while longer with no problems.

Problem: Usually if its really cold out or if the car sits overnight, I'll have a hard time starting the car and will be lucky if it starts up 10 minutes later... other times it just starts right up. Today I had no problems starting it and drove about 50 miles. Came home, turned car off for about 15 minutes, then went back to start it again... Engines starts to run but dies off immediately... Try starting again but doesnt turn... Try starting again, starts but extremely roughs, have to keep pumpin gas pedal to keep it alive, but the moment i let off the gas it dies off again.

Anybody have similiar problems? I'm thinking its fuel/ignition problem. Help please!

 

Sounds like you could have more than one problem. For the no start/no turn problem, is the SECURITY light flashing? If so, it could be an intermittent VATS problem.

For the idle issue, I would start by looking at the IAC - remove it from the TB and start the car (disconnect the electrical connector to the IAC first). It will idle really high, but should be smooth. If so try cleaning and adjusting the IAC and reinstall. FWIW - we had a 3.1 Lumina at work that had siimilar idle issues, would not idle unless you kept your foot in it. Turned out to be a bad ECM.

 

There is no security light, unless you're referring to the "INFL REST" light, which always goes on at first when i start the car no matter what

I'll check it, but whats the IAC again? I dont have my Haynes manual with me to look it up, also how do i adjust it

Dont think the ECM is my problem, that was replaced in hopes of fixing a different problem a year ago, unless something electrical blew it out again (which wouldnt surprise me)

 

You do have a SECURITY light if you have VATS. It does'nt stay on very long if the system is working correctly, which is why you may not have noticed it. Either that or the bulb is burned out.

The IAC is the idle air control valve on the passenger side of the throttle body. It's held in by two torx screws on the V6.

 

[quote=8492bird;3140765]For the idle issue, I would start by looking at the IACquote]


come on dude those things are factory set and even have a plug to prevent ppl from messing with it. only time it would be the IAC is if you just replaced the injectors or changed the fuel pressure. those screws have loctite on them so they cant vibrate out of position and if it was running fine a while ago then chances are its a sensor or a fuel delivery problem.

mayb start with looking at the air filters, then move to the TPS (throddle positioning sensor), if its out of alignment or if its broken down it sometimes wont show up on the idiot light. there are websites that show you how to check its alignment with a voltmeter and about a foot of 18ga wire. mayb also check the O2 sensor or even the EGR valve. but please dont be naive and just adjust the IAC to cover your other potential problems, you will lose gas milage and performance if you cut corners.

 

I'm not sure what you're talking about. The IAC is not factory set and does not have any kind of anti-tamper plug. The IAC is a stepper motor that extends and retracts based on a signal from the ECM to control idle speed by controlling the flow of air around the TB during idle. The torx screws are not held in by lock-tite either.