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2002 GMC Yukon XL Denali Question: no crank

 

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robsgirl4eva, Yuma, AZ, May 12, 2009, 00:23
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What are all the possible reasons to reference a problem relating to a system of "no crank"; what tests need to be conducted, and would a water pump and coolant be a logical solution for this problem?

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  • Answer #1

    May 15, 2009, 10:53
     Master

    You ask very interesting questions. There are extreme situations where a water pump or a coolant issue could cause a "no crank" condition but they are very remote. Before the starter motor can turn the engine, the engine must be mechanically sound. If coolant has gotten into the cylinders the engine won't turn over due to what is called hydo-lock, the liquid will not compress as the piston moves up in the cylinder and the engine will not be able to turn. The water pump shaft could freeze up and not turn, that could keep the serpentine belt in the front of the engine from turning which with keep the engine from turning over. Those are both very remote possibilities as is any mechanical issue that would keep the engine from turning over. The most common causes for a "no crank" issue are a faulty starter motor, battery, or battery cable issue. With all of the new electronic systems "no crank" issues related to computer issues have become more common. Listing all of the tests that could be necessary to properly diagnose a "no crank" condition on your Denali are to numerous to list here. If the diagnoses is not as straightforward as a battery or starter motor it may take a technician with a through understanding of the systems on your Denali to get to the cause of your "no crank" condition.

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