Compression Test

[XTCshri2222]

I searched on here didn't find a relitive compression test. While tring to figger out a problem on the car today i decided to pull out my compression tester:

Results:Cylinder1: 140 Cylinder2: 140 Cylinder3: 140 Cylinder4 137

test was done cranking the motor about 4-5times

what are the factory specs?

should be one my last questions for the week, lol I just been workingon getting this thing running 100% perfect while hauling a$$

[c-rad]

According to the FSM, standard compression is 171psi @ 350rpmThe service limit is 142psi @ 350rpm

So according to the FSM service specifications, you are in need of a rebuild. Try pouring a little bit of oil into the spark plug hole before you test the compression. If the compression goes up, your rings are worn. If it doesn't, you can suspect something in the head, but with all 4 low like that, it sounds like some bad rings to me.

[XTCshri2222]

According to the FSM, standard compression is 171psi @ 350rpmThe service limit is 142psi @ 350rpm

So according to the FSM service specifications, you are in need of a rebuild. Try pouring a little bit of oil into the spark plug hole before you test the compression. If the compression goes up, your rings are worn. If it doesn't, you can suspect something in the head, but with all 4 low like that, it sounds like some bad rings to me.

Either that or i got lucky and someone tossed in lower compression pistions I am burning oil, i figgered it's due to my turbo seal, i'll know better later in the week or next when that new turbo gets here and i can toss it on and see if the smoke stoped. I'll try pooring some oil in there se what happens

[capwred]

sounds like its time for some new rings to me.im rebuilding mine now.my compression was low like that and i decide before i put the bigger turbo on there i wqas going to make sure it was going to hold the power and not go booom.

[xyster]

Was the engine warm?

Was the throttle body held at WOT?

Those numbers are oddly consistent for being that low.

[jt15833]

yea, small variance between cylinders is just as important as having number in the right target range. wet compression test (oil) is a good way to check the rings while a leakdown test will do that too, but can find compression problems in other parts. make sure your engine is warm when doing so, on my engine itll be around 17in vacuum even if im at NOT for about 10-15 minutes then steady at 19in vac for the rest of the day : )

[XTCshri2222]

Was the engine warm?

Was the throttle body held at WOT?

Those numbers are oddly consistent for being that low.

engine was cold, and no throttle was applied, just cranked 4-5 times, fuel pump switch was off.

if it is the rings, i have a spare set of rings and a spare head gasket laying around. but I don't wanna go tearing it all open. do'h i'm redo the compression test with oil today.

[Nowhere]

Yeah, that's going to mess up your readings..

Have the engine hot (normal operating temp) and have the throttle body @ wot (wide open throttle)...

That should boost your numbers a lot..