2002 Pontiac Grand Prix GTP dies while driving

[mbutts]

Hello,
After googling this problem and no clear answers turning up, I've decided to see if anyone here can help me?

Our 2002 Automatic Grand Prix GTP supercharged coupe loves to stall/shut off on the road- usually when we are moving.
The Tachometer bounces up and down rapidly, then the car just gives out. It all happens very quickly and quietly. There's not a great deal of sputtering or rumbling.
At first we thought we were noticing a pattern in when and where the car would shut off: First we thought it only occured when coming to a stop, then we thought it was happening on inclines. However every time we think we've found a common denominator, the car just proves us wrong. Turns out it happens incline or not, and can happen while accelerating, coasting, or breaking. The most recent time it happened was in the middle of an intersection while accelerating. Other times it's happened while approaching stop signs, and merging onto a ramp or highway.

Here's the kicker: The car already has a ton of things wrong with it. The gas gauge is broken (always shows a full tank), so the check engine light was already on before this stalling problem started. In fact it's been on for over a year- (only because we never saw the need to fix the gas gauge as the elctronic display on the console shows fuel usage... and well we don't have a lot of money.)

We're coming to terms with the fact that the fix could cost more than a replacement car... I'm sick of this death trap of a car but we're not in a position to buy another one, especially since we wouldn't feel right selling this car for anything and it would be a total loss. Do you know what could be wrong with it? And do you have any idea how pricey the fix would be? Please help!

[MrCritical]

#1. This is not a car to be driving if you don't have money for repairs. It's can be fairly reasonable to maintain after every problem Is taken care of. I believe it calls for premium fuel.

2. When is the last time/mileage the fuel filter was replaced?

3. The fuel gage being broken is not the only thing probably causing the check engine light to come on. Get the codes read. Write them down in the order they come up on the code reader. Address the first code that comes up that doesn't have to do with fuel level.

4. No one can tell you from your description what is wrong with the car, or how much it's going to cost to repair. You don't have nearly enough information here for that kind of diagnosis. And if you don't get a good, accurate diagnosis, you'll be spending money on this thing 'till doomsday. If it's a high mileage car, just the required maintenance to keep it running correctly is expensive, and that doesn't count repairs when something goes wrong. The correct spark plugs, wires, and filters installed can easily run $500.

[demonspeed]

You may want to try perusing www.clubgp.com as they are dedicated to the SC'd Grand Prix. It's an 11 year old car, so these type of issues are likely not out of the ordinary. They may be easy to address, too.

Also, noting MrCritical's pricing -- note that it's installed. You could do much cheaper sourcing the parts and replacing them yourself. It's really easy to do, actually. Best of luck!

[Smaart Aas Saabr]

Jumpy tacho makes me think crank sensor? It wouldn't be a death trap if you fixed it when it was broken

[mbutts]

Wow, thanks for the input to everyone who posted.
I tried to give as much information as I could... I'm not a car person. I'm the owner's girlfriend, lol. Posted to see what kind of things GM enthusiasts could tell us about it. The car gets regular maintenence, tune ups, etc. and of course we use premium fuel...
Hummer04 it's good to hear from someone who's been in a similar situation. Many thanks.
Unfortunately the last few times we've taken the car into a GM dealer, they haven't been much help. We really do feel like we're "chasing gremlins". Maybe it's time for a new shop too. I think we'll try one this weekend.

[Hummer04]

We do not have a GM dealer where I live, It is an hour and a half away. The local garage really couldn't figure it out either when I was asking about it. I went online and asked a mechanic,on Ask.com (if I remember correctly) told him what I was experiencing. He replied more often than not that the ignition switch causes this problem. I am not saying 100% that it is but it is worth researching.My problem started once and a while, and then got progressively worse until it just wouldn't run anymore. When it did start, it sputtered and shut down. Anyhow I think this may be worth looking onto. A lot of mechanics over look the electrical end of things. There is a lot of electronics in todays cars and trucks, and if something is not working right, every thing else in that chain suffers, and may sound like a mechanical problem.
I know the local garage took note of my problem and will apply what they learned to other trouble shooting.
Good luck!!