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Old 04-17-2015, 03:06 PM   #10
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Join Date: Dec 2008
Location: Queensland, Australia
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I'm a little confused here (as normal)...surely a failed CPS won't make the engine sound like it has no compression when cranking.
The OP (rah rah) says in his opening question that the car sounded as though it was "cranking with low or no compression" which says to me that the starter motor was turning over the engine @ 600 rpm instead of 350 rpm) - just like if there were no spark plugs screwed in the heads.

While leak down tests are all well & good + more accurate than a simple compression test, as a couple of people has mentioned you have to get it right otherwise you can have some misleading results as with his comment "And EVERY cylinder is down 75-90%".

At this stage with engine out (which I think was a premature move) removing the spark plugs, opening the throttle body and conducting a simple compression test - even with a cold engine - will give some indication of the condition of the valve seating and piston compression on each cylinder.
I mean, this could be just a couple of cylinders that have collapsed hydraulic valve lash adjusters causing the starter motor to turn over faster than usual.....and yes the CPS can be the rout cause of the original problem too!
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