Hey guys I owned a 03 evo with 63k just got the car a couple months ago and decided to do a compression test the numbers came back from left to right 160-125-155-90 what could be the cause of such low compression also to note when I removed the sparkplugs they were pretty black on the thread and 2 and 4 had some oil on them ....car is mainly stock only mods are Walbro fuel pump ,,exhaust and intake ...any help would be greatly appreciated

 

leak down test will give you the culprit. either bad head gasket or blown rings

 

Or valves, valve seats, seals.

 

Ok I will try the leak down test

 

Hey man i,m in the same situation as you. I bought My Evo 9 with only 86k about 2 months ago and a did a compression test and my numbers were 140, 130, 100, 70. I then did my own leak down test and its my exhaust valves that are bad.

 

Thanks for the input man ...I'm gonna try to do the leak down test tomorrow and see what I find

 

When I did my leakdown test I put a long zip tie in the spark plug hole so that it was sitting on the piston but sticking out the top as well. Then I would just turn the ignition until it gets to its highest point (TDC) then test. Then repeat with every cylinder. That way worked best for me.

 

So I did the leak down test and I gettin a lot of air leaking for two cylinder walls and from the oil cap

 

That sounds like its your rings causing the low compression...

 

Yeah I ended up removing the cylinder head and just ordered the rings

 

Turns out my evo wasn't so stock after all after removing the pistons to inspect the lm it turns out it has wiseco pistons with eagle h beams