Q: If tdc is on exhaust stroke will it have 10psi on cylinder 1

asked by on December 19, 2017

The car shakes and runs rough on idle and seems like it wants to stall there was 10 psi reading on cylinder number one with a compression tester

Most engines will need at least a minimum of 100 psi per cylinder in order to run. In addition, for the motor to run efficiently, this also requires a variance of less than 10% from cylinder to cylinder on this reading. If you have a reading of 10% in one cylinder, this suggests you may have some serious damage to that piston of the compression rings for that cylinder may have collapsed resulting in that low compression reading.

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