2004 Grand Prix GT...Series 3 3800 NA (drive by wire)...completely stock...200k miles...car runs beautifully other than this minor starting issue.
You turn the key to start it...it fires, it sounds like it is running, so you let off the key. It dies immediately. It only does this when it is cold, and the colder it is the more times it will do it. Using a touch of throttle as it starts will resolve it. It has been doing this for 50k+ miles...but hasn't been much of a concern because it doesn't seem to be getting any worse, and it is so easy to get around it with a touch of the throttle. It is my mother's car. I stole it to get me home when the convertible died up in Michigan...and I would like to resolve a couple of the issues the car is having while I have it.
In the video below it failed three times, then I used the touch of the gas pedal to keep it going.
So...any idea what might cause this? Cleaning the IAC is the only thing that I can think of.
Edited to include a better video.
[This message has been edited by CowsPatoot (edited 07-19-2013).]
GreenPlatypus
JUL 19, 11:27 PM
Start by cleaning the throttle body and blade. The 3500 V6 with drive by wire also had a big problem with this. Butbe careful doing it. It is very easy to damage the throttle body. Turn the key on and have someone or something hold the gas pedal to the floor. Then go to town with your preferred cleaner of choice.
CowsPatoot
JUL 20, 01:39 AM
Sounds simple enough....would brake cleaner be an appropriate cleaner for this? If not, what would be recommended?
Slow6
JUL 21, 01:50 AM
Unplug the MAF and start it. Let me know what it does. Also another culprit could be the crankshaft position sensor which will cause the car to randomly die.
If you are going to clean the TB you would be better off using carb cleaner.
[This message has been edited by Slow6 (edited 07-21-2013).]
dematrix86gt
JUL 23, 02:09 PM
Carb cleaner makes O rings swell. use Throttle body and MAF cleaner. not hard on plastics or rubber. I would also check your Fuel pressure. if the pump is low pressure cycling the key can get the pressure up to starting point. works on failing 4.3 and 5.7 Vortecs to get you home.
carnut122
JUL 24, 07:40 AM
I'll throw in with the crank(cam?) sensor crowd.
[This message has been edited by carnut122 (edited 07-24-2013).]
Tstang429
JUL 27, 04:26 AM
Also make sure the battery is good. My wife has an 06 grand prix did the same dang thing aggrevated me to heck. Car had 60k on it. Got worse in cold Than one day noticed that it was cranking a little week. 6 months later middle of the summer battery failed. Swapped battery has not done it since. We also picked up close to 3mpg just by putting in a new battery. Testing battery I dont mean just the voltage make sure its cranking amps are good.
smartaxel
AUG 16, 03:11 PM
I'd check the MAF, Crank Sensor and IAC if it were my car, In all honesty, I'd swap out the IAC. That's a lof of miles on a mechanical part like that, who knows if it's hanging or sticking somewhere, or has some wear spot causing it not to adjust properly. In addition, I had to replace the MAF twice on my wife's car, and the crank sensor (DELPHI ONLY!) took care of a random stalling error. A non Delphi crank sensor for Advance made it even worse, and when swapped with REAL GM, it ran great!.
