Intermittent no start

2005 CHEVROLET BLAZER

150,000 MILES • 4.2L • 6 CYL • 4WD • AUTOMATIC

CSGTMAJ10

MEMBER
2 POSTS

The engine will not start periodically. It will run fine for a while then will not start. I will let it sit for a few days and sometimes it will start up, other times it won't. I have replaced the fuel pump and that seemed to do the trick but it's starting to do the same thing again. Leaving me stranded and having to tow it home. I let it sit for about a week and the battery ran down. So I hooked up my battery charger to it for a bit and tried to start and it cranked right over, ran for about five days and now it won't start again. has plenty of cranking power, battery is completely charge so it's not the battery.
Help.

Nov 26, 2019 at 8:17 PM

AL514

✓ASE Certified Mechanic
5,587 POSTS

Hello, this sounds like a crank sensor issue, an intermittent loss of signal from any major sensor like this will cause a no start condition. Sometimes when these sensors get hot they malfunction. Here's a quick check, when it's not starting , turn the key on, not starting, does the check engine light go out after a few seconds? And does it stay on while cranking? You can take it to a local parts store and they can scan the system for diagnostic codes. That's where you should start. But don't wait until the battery's dead, that will erase any codes.

Jan 29, 2021 at 11:21 AM

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