rezsst

Delete this if you want. Got a buddy with a 92 cx 1.5 d15b8. #1 50,#2-100 #3-75,#4-100psi. Obviously needs rebuilt. But could there be something else. Maybe timing belt.

mikey1

low compression can be caused by many different things, i cant tell from here,

- blown head gasket
- damaged valves
- valves not sealing/seating correctly
- burnt valves
- incorrect timing
- extremely worn piston rings (unlikely)
- cam not turning at all (broken timing belt)
- loose spark plugs

ezone

Cylinder leakdown testing should be the next step.

rezsst

Less than 150,000 miles #3 plug has alot of burnt oil on it.

Mad Dog Tannen

May be a bad valve or bad rings, do the leak down test.

rezsst

Thanks

92hatchbackcx

Hello, I'm the friend with the low compression. I am not familiar with the leak down process, how do you do this?

ezone

Welcome.

Googled:

https://mobiloil.com/en/article/car-...-leakdown-test

http://www.gregsengine.com/cylinder-...n-testing.html

http://www.hotrod.com/how-to/engine/...akdown-tester/

It's basically pressurizing each cylinder with air so you can figure out where the compression loss (cylinder leakage) is.

92hatchbackcx

Thanks for the help, it's much appreciated!

ezone

I'd sure expect stuck oil rings at the very least.
If the head gets pulled, that would be the ideal time to take care of the rings.