Pontiac Repair: Pontiac Grand Am 2000, crankshaft position sensor, cam shaft

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pervious question and answer:

Subject   CAR DIES WHOLE DRIVING/Starts after 1/2 hour
Question   2000 PONTAIC GRAND AM
HAD A TUNE UP AND OIL CHANGE DONE  WEEK LATER DRIVING CAR AT 75 MPH CAR JUST LOSES POWER DROPS TO 50 MPH AND STOPS, WILL START BUT NOT TURN OVER 3 ATTEMPTS.. HALF HOUR LATER OR SO STARTS UP WITH A KICK..
CAR TOWED, FUEL INJECTOR CLEANED.. FOLLOWING WEEK CAR CHECKED AGAIN FOR TUNE UP.. PLUGS CHECKED ETC ALL WAS OK ACCORDING TO THE MECHANIC.. ONE WEEK LATER AGAIN 75 MPH GOES DOWN TO 50 MPH WHILE FOOT PRESSED DOWN ON GAS PEDAL.. STOPS.. ATTEMPT TO START IT WILL TRY TO START AND DIE.. AFTER ABOUT A HALF HOUR IT WILL TURN OVER WITH A KICK..
WHAT COULD THE PROBLEM BE??  

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Answer   Hi Cassi,
This behavior has ignition system sensor written all over it. These sensors detect the position of the rotating parts of the engine and time the spark and fuel injection pulses accordingly. They are solid-state electrical crystals which fail in this manner of breaking down when they get warm, only to recover at cooldown. I am not familiar with the engines that might be in your Pontiac so I can't be specific as to where to look for them, but the chances are good it is the crankshaft position sensor, with a secondary possibility of the cam shaft sensor being the problem. It is an external device that can be changed in a few minutes in most cases and costs around $50. You can verify which it is by going to an Autozone Parts store where they will often due a free readout for fault codes stored in the engine controller, two of which will be specific for the crank and the cam sensors. Then you will know which to replace.
Roland

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asked question previously see above as to why car would just stop when driving, let it sit and then it would start up.
response was ignition switch. a new control module was put in and a few days later it happened again.  my service mechanic kept the car and ran it for a few days and the other day it just stopped again while driving,  this time it did not start back up again.  the mechanic put a new fuel
pump.  would this have anyting to do with the problem?
please advise
thanks

Answer
Hi
I would imagine from the post the fuel pump has not helped?
Does the vehicle turn on the "Service Engine Soon" light while this is happening? You stated the ignition switch was changed, was the Passlock sensor replaced also? Which
"control module" was replaced? Does the Security light come on or blink while it WILL NOT start?
The Fuel pump MAY be or have been your problem. I have experienced fuel pumps, and in these vehicles, that have acted very similar to this.
Please feel free to follow up post.
Hope this helps
Good Luck
Pawl