Compression test help

[97gsx_zeclipse]

I did a bunch of boost leak tests and for some reason it won't hold past 3 psi. Air was leaking out the dip stick. Changed the PCV valve to an OEM one. Checked the PCV and it wasn't leaking. I even turned the crank 30 degrees and still won't hold. So I'm guessing I have blowby. Did a compression test but didn't put a spoon full of oil in each cylinder. Cranked each cylinder 8 times and got these numbers. 180-175-155-130. Any ideas?

 

[dsm_racing]

Possibly a head gasket. How many miles on the motor? Do you have any previous compression test results? Try the test again with oil in the cylinders just to possibly exclude a variable.

 

[97gsx_zeclipse]

Maybe it is a head gasket. If it was a head gasket, wouldn't all the cylinders compression be bad? There is only 47k on the new motor.

 

[dsm_racing]

No, if you blow a head gasket, it can be either between two cylinders, or from one cylinder to an oil or coolant passage.

 

[97gsx_zeclipse]

Will a leak down test find exactly what the problem is?

 

[Cs4g63]

A leak down test should be able to tell you where your problem is.

 

[97gsx_zeclipse]

Ok I looked through the repair manual and it says that if I have bad compression, that I need to do a leak down test but doesn't say where in the manual. Anyone know a vfaq on it or the page number? Thanks

 

[cbassgsx]

http://www.dsmtuners.com/forums/showthread.php?t=97401