Hi everyone, wondering if you could assist me in this matter.....

I tried to diagnose a basically dead #1 piston. The plug is always clean, and the headder primary does not get hot like the others.

Test 1: Put the compression gauge on, and gave it about 4 turns and got about 152 psi. (Motor cold, and Throttle blades closed).

Test 2: About the same, and the same manner as test 1.

Test 3: I cranked the engine with the gas pedal fully depressed (Throttle blades fully open) and only got about 32 psi. I got this result twice also.

All the tests were done with the engine cold, no fuel or spark. What confuses me, is why would it only register 32 psi with the Throttle blades fully open. What I understand is that a compression test should be administered with the blades fully opened.

So what does these results mean? Sticking Intake valve?

Thanks GUYS!!!!

 

Can't say for sure what that means, but a leakdown test would be the best thing to run on it.