engine cranks very slow ?

2007 CHEVROLET TRAILBLAZER
179,899 MILES • 4.2L • 6 CYL • 4WD • AUTOMATIC
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FREDDFITZZ
My engine cranks very slow will not start new battery new starter
Feb 28, 2026 at 10:53 AM
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STRAILER
  • ✓ASE Certified Mechanic
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  • ASE Certified Mechanic
So what I would do first is try to bar the engine over with the spark plugs out, it should have a fair amount of resistance, if you cannot rotate the engine over there is internal damage to the engine. Also, check the positive battery cable and the ground to the engine, these must be in good shape for the engine to crank over strong enough to start. Please use this video to help.

https://www.youtube.com/watch?v=oN42gZN6gOE

Please upload a short video in your response of the problem, so I can see what's going on. Ken
Mar 1, 2026 at 11:37 AM
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