2004 Grand Prix will not start!

[sshellzr21]

Background:

Boyfriend was driving to work and came to a stop. He went to hit the gas and the engine stalled. All the electrical was still on in the car and it was in drive. He put it back in park took the key out and tried to start again - nothing. You can crank the car but it does not turn over.

He pushed it to a safe spot and we had it towed home. The diagnostic test gave a "Throttle Body Module Error." We've since replaced the throttle body and the ignition switch. I have reset the security system with by turning the vehicle to the ON position leaving it for 10 minutes, turning to OFF, wait 5 seconds and repeating two more times. Directly after doing that the key now STICKS in the ignition when cranking. You crank the car, let go, and the key will continue to crank the car for about a 1-2 seconds after you've pulled away. Since replacing the throttle body the dash is now also reading "reduced engine power".

We're all convinced it's something completely stupid and a semi-easy fix. Let me know you're thoughts! (After I reset the security system and there was no improvement we unplugged the battery for 30 minutes to try and reset the system. There was no change.)

Do you think we received a bad throttle body? It sounds worse when cranking now than it did with the original throttle. We did not have the reduced engine power error before replacing the throttle body either.

PS. We've had previous problem with hard starting with this vehicle and had work done (replaced catalytic converter and cleaned the throttle body). It has worked great since we had it serviced and has never stalled until now.

PLEASE HELP!

[industrialfish]

One thing I know, is the ignition is supposed to "stick" like that. It's not like older cars where the ignition switch is mechanical. Ours is just a button that tells the computer to start crankin'

Is the fuel pump kicking on? 60ish psi at the fuel rail?

[sshellzr21]

Yes, you can hear the fuel pump working if you're underneath. You can also smell gas if you try to push the pedal while starting.

I asked around and none of us knew that a new throttle had to be programmed. Duh... We're going to try that and see if it helps but I have my doubts. The tech said that the "reduced engine power" is normal if the throttle has yet to be programmed because the system is not recognizing it.

He told us that the key sticking is normal too, so that's good to hear. The old switch did not do that so it may have been part of the problem.

[SDGTP99]

So when you turn the key it starts then dies? What Troubles codes were/are you seeing? Have you done any mods or work on the car recently?

[SDGTP99]

Does it stay running if you keep your foot on the gas?

[sshellzr21]

No, turning the key just makes a cranking noise. The engine has not turned over since it stalled. The only trouble code we had was "throttle body module". We've replaced that and I was told that I'll need to get it programmed. Holding the gas does nothing but make the surrounding area smell like gas and make the exhaust have this *puff* sound.

We found out yesterday it's getting gas but not spark. It looks like the coil pack module is the problem, not the spark plugs. Does anyone have experience with this problem before? What did you do? Should I replace just the module or the module and coil packs?

My mechanic is going to come back out on Saturday and do another diagnostic test. I'm worried that if the coil packs were the problem why didn't it show on the last test he did?

[sshellzr21]

Oh, and no, no mods were done to this vehicle.

[rickisrad]

Oh, and no, no mods were done to this vehicle.

I had this issue before and it was a bad PCM. If it is a comp g I have one for sale.

[aceswild961]

my 2004 same thing went to another gtp site this is a major problem with these cars all years
soon as i fix mine it's gone

[sshellzr21]

my 2004 same thing went to another gtp site this is a major problem with these cars all years
soon as i fix mine it's gone

We replaced a coil pack and new ignition module. It now runs better than it ever has before. Agreed, we’re selling ASAP.

[industrialfish]

Jesus ****ing Christ. It's a 14 year old car. It's going to start having problems like any car its age.

[rickisrad]

Jesus ****ing Christ. It's a 14 year old car. It's going to start having problems like any car its age.

LOL. I agree. Why would you go buy another used piece of crap that you have no idea what was done with it?? Unless you are going new or much newer, stick with what you know.