So i did pressure test for my evo 8 that has around 180k km and the results were-

Cyl 1 - 180 psi
Cyl 2 - 160 psi
Cyl 3 - 170 psi
Cyl 4 - 140 psi

Tests were done with warm engine
Can someone tell if i have to worrie about it and start thinking about rebuild or is this fine

 

#4 seems a bit on the low side. Re-run the test but add a cap of oil into the cylinder to see if that pulls up the number. That will let you know if its rings or in the head.

A leakdown test would be a good idea too.

 

Service limit on compression tests are usually around 125 psi. I think someone can fact check that but I believe thats what it is if I recall correctly.