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Compression test - VP 3.8 II

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strgas

GRA = REAL HP
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last vr v6 i did comp test on had 240 000 kms and came up with 205 to 210 psi across the pots , if theres less then 15 psi difference between the highest and lowest readings engine is consider in good condition , age wear and tear temp will all make the readings different even a battery low in charge will give lower readings when cranking the engine over allow aleast 6 -8 rotations of the engine on each cylinder , always compare the total readings of a given engine and rely on the cars manual as a guide to specs and tolerances given from factory engines and not high milage engines
 
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The way I was told to do it is take out all spark plugs, test each cylinder (I do each cylinder twice, just to be sure) and then wen all cylinders are tested then put all your spark plugs back in.

I usually crank for about 3-4 seconds (that's me).
Hi I read your post and you can crank 5 to 6 times and even more. It will just hit your same psi! Did it jumpier quick on first crank and slower on other cranks? Also throttle needs to be to mashed wide open
680 kpa (100 psi) is what the workshop manual says for ecotec.
 

Immortality

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You are responding to a 9 year old post!

Please don't dig up old threads unless you have something useful to add.
 
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