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jj7
04-08-2005, 05:08 AM
I am preparing to do the compression test for my car,never done such a thing before, i gathered some info about the procedure,and got some steps to be cleared if possible:

1- Is it better to disconnect all the coils and spark plugs,or is it better to test one cylinder at a time?
2- After the fuel system is disabled, and pressing the gas pedal then cranking the engine,do i crank till the gague holds to the highest reading,or there are nomber of strokes should be accomplished; 4,5...?
3- Are there any cautions or any additional tips for this procedure?

TIA

jj

632 Regal
04-08-2005, 11:41 AM
I disconnected the ECU and removed ALL the plugs and wires (boots on mine). I cranked 3 turns for each cylinder, and when done repeated the test for accuracy. Disconnecting the ecu pretty much insures you wont fry it.

jj7
05-01-2005, 04:23 AM
Finally, today i carried the engine compresion test,as follows:

1- take the car for a spin till reaching operating temperature
2- take out fuse 23 till car stalled
3- disconnect battery
4- disconnect ECU
5- disconnect coils and spark plugs
6- connect the gauge
7- step on the pedal and give 3-4 cranks

I was alone doing that,i managed to see the needle jumping with each stroke, all the six cylinders went up to almost 10 BAR ( around 140-145 Psi), the compression didnt hold the needle steady,but after each stroke it went back to (0).

did i miss anything than having another extra hand around,and are the results satisfactory?

PS: after all is finished and everything is put back in order,the car operates :D

TIA

jj