Knocking when starts and stalling when warm

2005 CHEVROLET BLAZER
160,000 MILES • V8 • 4WD • AUTOMATIC
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WILLR
  • MEMBER
  • 2 POSTS
When I first start the engine, there is a loud low tone knocking sound that goes away. Then after the engine is warm it tends to stall out and is sometimes hard to restart.
Jun 24, 2018 at 3:43 PM
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STRAILER
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 54,178 POSTS
It sounds like the engine is starting to wear. I would start by changing the oil to a heavier weight like 20/50. Here is a guide that can help:

https://www.2carpros.com/articles/how-to-change-engine-oil-and-filter

This guide will help with the stalling:

https://www.2carpros.com/articles/stall-at-idle

Please run down these guides and report back.

Cheers, Ken

Jan 29, 2021 at 11:21 AM
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WILLR
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The knocking noise sounds like it comes from the upper area of the engine and only last for one to two seconds. The stalling problem occurred at the same time the knocking noise. They seem to be related. What one item would cause both problems?
Jan 29, 2021 at 11:21 AM
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STRAILER
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 54,178 POSTS
It sounds like the timing chains and guides need to be replaced. Is there a chance you can make a quick video of the noise and upload it here in your response we have the capability? That way I can be sure and can get you instructions of what it will take to fix.

Please let us know.

Cheers, Ken
Jan 29, 2021 at 11:21 AM