Crank sensor has no power - Engine not starting?

TERRY CALDWELL

MEMBER
1995 GMC JIMMY
4.3L
V6
4WD
AUTOMATIC
182,000 MILES

Took through the car wash ran while washing it shut off when I put it in gear, started it back up and took it down the highway where it shut off while coasting. Crank sensor has no power when starting but power when key on. Faulty crank sensor or wiring? Where does it draw power from/what computer controls it?

6 Replies

KEN L

MASTER CERTIFIED MECHANIC
48,397 POSTS

The first thing we need to do is check all fuses with the key on. here is a guide to help with the fuse locations in the diagrams below:

https://www.2carpros.com/articles/how-to-check-a-car-fuse

If all fuses are good, you may have a PCM that went out. The crankshaft sensor is solely controlled by the PCM, this is why we need to check the power fuses to it. Check out the images (below). Please let us know what you find.

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Sunday, January 29th, 2023 AT 6:23 PM

TERRY CALDWELL

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4 POSTS

Replaced crank sensor, when that didn’t work stuck a fuel pressure gauge on there out of wishful thinking and discovered 10lbs of pressure. I found the problem but thank you for helping.

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Sunday, January 29th, 2023 AT 7:51 PM

TERRY CALDWELL

MEMBER
4 POSTS

Replaced crank sensor, when that didn’t work stuck a fuel pressure gage on there out of wishful thinking and discovered 10lbs of pressure. I found the problem but thank you for helping.

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Sunday, January 29th, 2023 AT 7:51 PM

KEN L

MASTER CERTIFIED MECHANIC
48,397 POSTS

Nice work, here is how to change the fuel pump out in the images below but I would check the fuel filter as well. Here is how to drain the tank:

https://youtu.be/Q5MH2gnyFH0

Do not remove the fuel tank with gas in it. Check out the images (below). Please let us know what happens.

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