engine makes knocking noise

2002 CHEVROLET TRAILBLAZER
274,479 MILES • 4.2L • V6 • 4WD • AUTOMATIC
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ARNOLD LEACH
  • MEMBER
  • 1 POST
I was driving today and the engine died, when I went to start it and made like squealing noise. When trying to start it had trouble getting it to turn over then when it did start sounded like it was knocking. It never lost power and holds a oil pressure of 40 when idling and noise is coming from near top of the engine. It looks like the drive belt on the engine had been hot. The clutch on radiator fan has been going out past three months and fan is hard too.
turn what could it possibly be
Jun 20, 2016 at 11:06 PM
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JACOBANDNICKOLAS
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 110,190 POSTS
Under higher temps, the clutch fan will be harder to turn. Since the engine is hard to start, try this. Remove the serp belt and see if it starts easily and without noise. PLEASE NOTE: DO NOT run the engine like this longer than a few seconds just to see if it makes a difference. Based on your description, it sounds like something belt driven is locking up or is locked up. Let me know what you find.
Jun 23, 2016 at 7:43 PM
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