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Ted G.
Ted G., ASE Certified Technician
Category: Pontiac
Satisfied Customers: 6159
Experience:  30 years auto repair experience, ASE Master Tech. Expert Witness.
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Pontiac Grand Prix GT: I have a 2001 Pontiac Grand Prix GT

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I have a 2001 Pontiac Grand Prix GT with super charger. Often times it will not start. The engine turns over well as if the battery is charged just fine. Sometimes even though the engine turns over well without a jump, if I jump it, it will start but not all the time. When it does start and I rev the engine to about 4000 rpm it starts missing. It appears to miss on all cyl. When I drive the car at about 50+ miles an hour it starts missing and or lurching. When the keys turned on the fuel pump comes on pressures up and stops but appears to be weak.
I would suspect a bad fuel pump from what you describe. One test you could try before you go out and get hold of a fuel pressure gauge is if the car won't start on the first try, cycle the key on and off three or four times and then try to start again. If the system is losing pressure that will build it back up and start the car. (I suspect it is not the jump start, but the key on and off a couple of times that is starting it.) The fuel pump is not governed by pressure, it is a timer, so even though it stops on prime (key on) it doesn't mean there is adequate pressure. Low pressure due to a bad pump will also cause your miss over 4000.
Customer: replied 4 years ago.

Thank You for the answer. The one point about the trying to start. I do try cycling but it seems like the engine is not getting fuel. When I go the fuel pressure test route what should the pressure be??

My spec shows 56-62 psi, and it should hold over 30 psi for about 10 minutes after shut down. It could be the fuel pump actually has a dead spot in it (very common on GM) and when you hit it the thing just won't activate or spin properly.
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