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Eric
Eric, Automotive Repair Shop Manager
Category: Pontiac
Satisfied Customers: 24269
Experience:  20+ yrs. experience as repair shop manager and technician.
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2001 Pontiac Grand Prix: stall..distributor/rotor..sensors

Customer Question

Mu son has a 2001 Pontiac Grand Prix that has started to stall while driving. He has to pull over for a few minutes then get started again and after about 10 -15 minutes the car cuts off and he has to repeat the aforementioned steps again. He has had a complete tune up from a mechanic, (wires plugs, distributor/rotor, replaced the ignition / crank postion sensors,) and the problem still exists. The mechnaic is stumped, he says the fuel pumps are working, fuel regulator is working. No codes are thrown from the engne stall/cutoff. Could it still be a bad fuel pump with out any code lights? The car idles fine for awhile then cuts off. My son hs spent about $1k trying to get his car fixed and yet the mechanic is stumped while my sons bank account gets drained. what could the problem still be?
Submitted: 3 years ago.
Category: Pontiac
Expert:  Eric replied 3 years ago.
Hi,

yes, it could very easily be the fuel pump. They can overheat and shut down, requiring anywhere from 10 minutes to an hour to cool down before they will function again.

there is a very simple test your son can do and will cost him about $5 for a can of starting fluid. He needs to carry the can with him and the next time it shuts off and wont restart immediately, he needs to spray some starting fluid into the throttle body opening and try to start it. if it starts and runs for a few seconds, then it has spark and no fuel, which means that the fuel pump is shutting down and needs to be replaced.
Customer: replied 3 years ago.
Do you know where the fuel pump is located on this vehicle? Gas tank or external?
Expert:  Eric replied 3 years ago.
Hi,

gas tank, there is an access panel underneath the spare tire to access and replace it from there without dropping the tank
Customer: replied 3 years ago.
would you know what an internal pump would cost him?
Expert:  Eric replied 3 years ago.
Hi,

Depending upon brand, the fuel pump will run from $285 to $375.
Customer: replied 3 years ago.
Since the cutting off happens as I have described what would the chances of it being the computer?
Expert:  Eric replied 3 years ago.
Hi,

slim, although possible. but based upon your description, it is more likely the fuel pump overheating, as this is a fairly common failure
Customer: replied 3 years ago.
Would a clogged fuel filter cause this cutting off. Although a new fuel filter was installed, does this vehicle have more than one fuel filter? Thanks for your patience!!
Expert:  Eric replied 3 years ago.
Hi,

if it were a clogged filter, it wouldnt be a case of shutting off, cooling down for 10-15 minutes and then restarting.

there is just the one filter underneath the car.
Eric, Automotive Repair Shop Manager
Category: Pontiac
Satisfied Customers: 24269
Experience: 20+ yrs. experience as repair shop manager and technician.
Eric and 8 other Pontiac Specialists are ready to help you
Customer: replied 3 years ago.

Eric,

 

Thank you very much for your expert advice!!

Customer: replied 3 years ago.

If positive ful pressure remains constant from the fuel pump, could a bad EGR valve create a vacuum producing the sypmtoms I described?

 

thanks

Expert:  Eric replied 3 years ago.
Hi,

although I have seen egr valves cause driveability problems such as hesitation, I have not seen one cause the engine to shut off

If spraying starter fluid into the throttle body doesnt make a difference and still not cranking, then we have fuel but no spark. I would suspect either ignition coils, or more likely, the ignition control module
Customer: replied 3 years ago.

The car starts and remains running for a while then cuts off. Fuel pump was checked and positive fuel pressure remained constant when running and did not wane. All lines were checked for vacuum leaks none noted. Checking EGR valve when car cools down! Anything else we can check? How could we check the computer module for proper functionality?

Expert:  Eric replied 3 years ago.
Hi,

the computer can only be swapped out for a known good one. Even with a scanner, it isnt possible to see if it is the cause.

checking the fuel pump pressure when running wont show us anything as it is working at that point.

we need to see what happens when it shuts down and doesnt restart immediately. That is why we spray the starting fluid into the throttle body. if it starts and runs on the starting fluid, then we know it has spark, but no fuel and therefore we know the fuel pump is overheating and shut down.
Customer: replied 3 years ago.
Eric, when the car is idling will it take longer to produce enough heat to shut down the fuel pump, letting the car idle long enough would eventually shut the punp down versus driving the car and then the pump shuts down and will not immediately restart for another 5-10 minutes. We are in NJ and it is very cold here
Expert:  Eric replied 3 years ago.
Hi,

unfortunately, the only way to test is when it shuts down, otherwise everything tests good. that is why your shop wasnt able to find anything - they were testing when it runs.

I would drive it until it shuts down, then pop the hood and spray some starting fluid in the throttle body - if it starts and runs for a few seconds, then you have confirmed that the fuel pump is overheating and shutting down

the only way to do it is this way. i know its frustrating, especially with the cold weather, I have to deal with the cold here in South Dakota, so I do understand.
Customer: replied 3 years ago.

Eric

 

South Dakato, hell its warm in Jersey compared to there! Do I need to pay another whole payment for the same answer!

 

Thanks Eric

Expert:  Eric replied 3 years ago.
Hi,

no, all these is just considered followup and is covered under the original price. Only if we switch topics(like asking about brakes) would you need to pay again.

and yes, it does get cold here. hard to believe but i moved here from Florida and wouldnt go back if someone paid me...
Customer: replied 3 years ago.

Eric,

 

Thank u very much for your time and patience!

 

Stay warm brother,

 

Mark

Expert:  Eric replied 3 years ago.
Hi,

glad to help, and if you run into any problems on this, I am here everyday but sunday to help people save some money on their cars
Customer: replied 3 years ago.

Eric,

 

We drove the car on the highway, it did cut off after a while, and after 10minutes or less it started back up. The mechanic says the fuel pump has mainmaintained good pressure throughout, shether idling otr whe it cut off. Does this vehiclel hav ethe trational cap/rotor or coil packs?It lookis as if it has coil packs . Could tyhis be the cause? I know the mechanic chnaged the wires and plugs but not the packs . we c;leaned teh trermionals on the battery just in case. Buthe vehivle still cuts out. My son has said tht when it recently cutoff, while coasting to a spot he stepped on the accelerator and the car restarted back up before he came to a full stop. Do you sitill believe it is the pump or would you now start to lean towards the computer. Again, no codes or lighs have gone off!

 

Thanks

 

Mark

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