I Need Help Please....

[JeanBean]

I have a 2004 Grand Prix GTP and it started missing real bad but only when my car is idling. I had the spark plugs and wires changed but it still doing it. Can anyone help me with this please.
Also i had my transmission rebuilt and since then my key less entry doesn't work. You can hear it clicking when you press the button but it doesn't do anything.. Please let me know if you have any idea of whats going on..
Thank You

[TheOtherNick]

sounds like a vac leak. Spray around with carb cleaner untill you find it.

[JeanBean]

Thanks but can u tell me whats a vac seal..lol..

[cerick08GP]

Hmmm, where to start. The trouble shooting method he suggested is how to check for a vacuum leak. There really is no specific “seal”; however the entire intake system is sealed from the atmosphere (just keeping it simple guys!). If the carb cleaner gets pulled into the system through the leak the engine will speed up, hence revealing the location of your “vacuum leak”.

Anyway back to your problem, my personal guess is you have a failing fuel injector.

Is your idle high or low? Or normal?
Is the idle steady, or does it cycle?

[JeanBean]

It idle normal.. But my whole car shakes because it misses so bad.. it was knocking for a short while but now it not.. i don't know whats going on..

Thanks For All The Help

[cerick08GP]

Just to eliminate some causes here, you are using premium gas right? You need to use at least 91 octane or you’re begging for problems.

Did you check for vacuum leaks?

Also, are you sure it is missing? And not just vibrating, because I’m a little lost on how a car could badly “miss” and idle normally. If it is simply shaking at idle, you probably have a bad motor mount.

Beyond all that, you really need to get your car scanned for codes. Otherwise this is going to take a long time to fix. You can buy a scanner for like $50, or you can take it to Autozone and they will scan it for free.

[stretch1976]

Check the coil packs...scanning it you'll get the O2 sensor and spark plugs.