Need help with compression test readings

[Demon5spd]

OK guys i'm pretty much stumped, I decided to do a compression test just to ck out the health of my motor and my reading kind of worry me.

I did the test per this forum making sure the throttle was open ect...

Well the readings for 3 of the cyclinders aren't that bad but one of them is off the scale.

Here's the readings.

cycl 1- 145
cycl 2- 147
cycl 3- 140
cycl 4- 15

As you can see cyclinder 4 is only reading 15psi which is really really bad.

I rechecked it several times and then rechecked other cyclinders to make sure my guage didn't mess up but in the end cyclinder 4 is still only.

So my question is what could be causing it to be so low the other cyclinders are low but not that bad.

There is some smoke coming out the back when i shift but my turbo seals are leaking so i thougt that was the reason for the smoke, but other then some smoke the car runs great and has alot of power and idle's really good so i'm stumped.

 

[steve]

So my question is what could be causing it to be so low the other cyclinders are low but not that bad.

Burned or bent valve, damaged piston or ring. The next test would be a leakdown on that cylinder to see where the air goes.

Steve

 

[Demon5spd]

Thats what i was afraid of.