Started shut down two days ago while I was driving?

MRBLOV

MEMBER
1992 PONTIAC GRAND PRIX
6 CYL
2WD
AUTOMATIC
100,000 MILES

My 1992 Pontiac Grand Prix started shut down two days ago while I was driving and would only start after I waited several hours. After restarting it and geting it home I parked it. I was anle to start it the next morning and drive approx 7 miles and park it at my job. After leaving it parked all day I attempted to drive it home and after approx. 3 miles it again shut down and I had it towed which took about 1 hour. I attempted to start it several times but it would not start. The following day I went back and attemped to start it and it started. What could be the reason and approx. How much will it cost to repair. It is an old car and I don't want to sink too much monet in it because there are other small problems.

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

It sounds like you could have a faulty crankshaft position sensor.
Over time with heat and vibrations from the engine the crank sensor can lose its internal calibration. Which will cause it to send error signal to the ECU. That can trigger an engine shut down.
When a crank sensor fails it can shut the engine down as you are driving down the road.
After the shut down the engine may or may not start back up. Sometimes it will start up at the beginning but then it will stop working completely.

Here are some helpful articles:

https://www.2carpros.com/articles/how-a-crank-shaft-angle-sensor-works
https://www.2carpros.com/articles/symptoms-of-a-bad-crankshaft-sensor
https://www.2carpros.com/articles/crankshaft-angle-sensor-replacement

I have attached diagrams for your reference.

Please let me know if you have any questions.
Thank you.

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