Starts but let go of gas pedal and shuts off.

[speedymjsg]

Hello everyone. Need some help with this one. I tried turning on my car this morning and it started and shut off like in 3 seconds. I tried and tried starting again until I ran down the battery. Nothing. Would crank over but didn't start.

Now, when I got home from work I had my cuzin give me a jump start. After about the fifth try it started. Had to pump the pedal a lot but it started. I held the pedal down for about five mintues and it stayed on, but as soon as I let go of the pedal the car turned off. Any suggestions?

Just as a note: Don't know if this is any help, but I use premium gas on my car because it's supercharged and yesterday I accidently put in $20 of regular gas.

[jonsonton]

What year is it?

It almost sounds like a vacuum leak. Do you hear any "hissing" when trying to start it? It could also be an internal vacuum leak such as the IAC sticking. Im not saying to replace it, but you could try tapping on it lightly, if it is stuck, and hopefully put it back to normal, at least long enough to get it started. Good luck.

[speedymjsg]

It's a 92 Park Avenue Ultra 3.8 Supercharged Engine w/ 122k

What's an IAC and where can I find it? Sorry, not to good on cars yet. Still learning. Thanks!

[speedymjsg]

OK. New info. I now get my car started sometimes. When I do get it started it stays on now. I drive it around the block fine, come back turn off and start the same thing. Starts after trying a couple times and letting it sit for a minute or two.

My check engine doesn't stay on when I have the car turned on, but it stays on if I only have the switch on. I checked to manually for codes just in case and I pulled out a 13 and a 14 which I believe is (Oxygen sensor, and coolant temp sensor circuit). Also the coolant low light has been on for about 2 months. Forgot to mention that. Please help!!

[auto trainy]

Have you been adding coolant recently?

[HotZ28]

Fortunately, this is an Ultra SC engine and has an aluminum intake, therefore it is exempt from the UIM coolant leak.

When it is not starting, do you have spark? The TPS has nothing to do with spark, however, you need to check the voltage on that also. A broken spring on the TPS will cause the TPS to sit in a random position and will not return with the throttle position. Look at the lever on the TPS and see if it moves with the TB.