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2001 Chevy Express 8.1l randomly dies

Bigears270

By Bigears270
in Ask A GM Technician

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Bigears270 Enthusiast

Bigears270

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I have a 2001 Chevy express w/ 8.1. It randomly dies and sometimes will start right up again and sometimes not. I have replaced the fuel pump, fuel filter, and pig tail connection for the pump. That did not help! I then replaced the ignition switch, plugs, and wires same thing did not help. When it does die and won’t start for a while I have spayed starter fluid in the air breather and it will try to start. So I know I have a fuel issue and not spark! The only things I can think of are the cam sensor, crank sensor or the ECM. Any ideas or help would greatly be appreciated. This is my handicap van and my only transportation. Thanks

gshawbud New Member

gshawbud

Posted
Posted

I had this issue before, although it wasnt a gm vehicle it was the distributor cap, it had a hairline crack and was allowing moisture in. somthing to think about.

Chiefmorton Enthusiast

Chiefmorton

Posted
Posted

I had a 2001 2500HD with the 8.1 and it started doing the same thing. I would be driving down the road and bam just like someone turned off the key. I would cost off the road wait a couple minutes and it would fire right back up and away we'd go, might not do it for a few days and then it would. I researched the heck out of the problem and found on a couple other forums that the culprit was the crankshaft sensor.

 

My dealer did just as some forum members mentioned they questioned me on why I thought it was the crankshaft sensor and wanted to plug it in to make sure (another $80.00). I stood my ground and told them I had done enough research and felt certain it was the sensor and wanted it replaced. I would've replaced it myself but have been told it's a booger to get to. The dealer replaced it and it never died again.

Bigears270 Enthusiast

Bigears270

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Hey thanks for responding. I should have looked through the forum a little harder on this issue, next time. I had my father pick one up today in town, so hopefully get it changed out tomorrow. I guess one nice thing about a van; it’s easy to get at this sensor. Thanks again.

ChevyTech77 Senior Enthusiast

ChevyTech77

Posted
Posted

X100 for a crank sensor.

 

When the head of the sensor snaps off, while trying to extract the sensor from the block, screw a long drywall screw into the center of the sensor, soak the area with penetrating oil and continue to "work" the sensor out of the block while adding penetrating oil along the way. Not a fun job but not the end of the world either.

Bigears270 Enthusiast

Bigears270

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Changed the sensor out yesterday, and it went better than expected. After spraying the hell out of it with panther piss, and letting the engine run for a while so it wouldn’t be too brittle since it was 15 degrees out. It popped right out new one went in and buttoned it all back up in 45 min. I am glad it didn’t snap off! Good idea about the drywall screw if it did. Drove it 60 miles or so today and no problems at all. Hell it has never ran these good since I have owned it. Thanks again!

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