redoing leak down test, got question

[truwarrior]

Yesterday I did a leak down test on my car. I alighed the timing marks and tested cylinder 1 and 4. Tested ok. Next I turned the crank until cylinder 2 and 3 were tdc. I tested cylinder 3 and it was ok. Next I tested cylinder 2 and the air just poored out of cylinder #4.

First is this the compression stroke of 2 and 3 or is it the exhaust stroke? Also Why is air coming out of cylinder 4? Thanks for any help on this one guys!

WTF

 

[truwarrior]

Well turned out I tested cylinder 2 on the exhaust stroke and not on the compression stroke. Did the test again today anf got 85psi out of 90 psi on the test. Compression test vaired across the board from 150-160. So it looks like some leak between the rings but not to bad.

 

[Big Woo]

Well it looks like your leak down rate is 5.5%

Since the firing order is 1,3,4,2

When #1 is at TDC of the compression cycle, #4 is at TDC on overlap, or between the end of the exhaust cycle and the beginning of the intake cycle. #3 would be at BDC of the intake cycle, and #2 would be at BDC of the power cycle.