Engine shut off while driving

BIRDIECGARCIA

MEMBER
1999 GMC YUKON
5.7L
V8
4WD
AUTOMATIC
350,000 MILES

Months ago, while driving the truck shut off numerous times. It turned back on. Never fixed the problem. And two days ago it turned off on the interstate and will not turn back on. The fuel pump is working and shoots fuel to engine or whatever it is called. And replaced the alternator and still will not turn on.
Help?

4 Replies

ASEMASTER6371

MECHANIC
52,797 POSTS

Good morning.

When you crank the engine, does the tachometer move up a little while cranking? That will tell us if the crank sensor is working.

Roy

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Tuesday, March 20th, 2018 AT 4:58 AM

BIRDIECGARCIA

MEMBER
2 POSTS

Yes. It barely moves.

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Tuesday, March 20th, 2018 AT 9:24 AM

ASEMASTER6371

MECHANIC
52,797 POSTS

Okay, the crank sensor is sending a signal to the PCM.

The next is to check fuel pressure. You can rent a tester at a parts store to verify correct pressure.

Beyond that you will need to check to see if the injectors are being commanded on by using a noid light. That also can be rented at a parts store as well.

Roy

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Tuesday, March 20th, 2018 AT 9:27 AM

RENEE L

ADMIN
1,260 POSTS

Hello BIRDIECGARCIA,

Thank you for visiting 2CarPros. Here is a helpful link to an article from this site with step by step instructions and pictures explaining the process of checking the fuel system pressure, regulator and fuel pump in less than fifteen minutes:

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

If you need further assistance please come back to the site we are always happy to help.

Kindest regards,

Renee
Admin

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Tuesday, March 20th, 2018 AT 2:59 PM