Well I finally did a compression test. <img src="/forums/images/graemlins/rolleyes.gif" alt="" />

Results;

#1 150
#2 155
#3 150
#4 160

This was after 4 cranks like the book says. I was cranking from in the cab so IÆm not sure how quickly the pressure came up but from the numbers I think its ok.

Book says 142 to 170 are OK.

So now IÆm not sure what the problem is. <img src="/forums/images/graemlins/confused.gif" alt="" />

The book says the vacuum should read from 17 to 22 inches. I was reading 19 so vacuum looks good.

Well after reading some in the manual I think I might have clogged exhaust??? ItÆs the only thing I have left that would seam to fit the problem.

And after looking at the exhaust I see that it only has one O2 sensor? I thought even OBD1 where supposed to have two? One in front of the cat, and one behind?

Anyway I think IÆll try loosing up some of the screws on the exhaust header output where it meets the rest of the exhaust so it can leak abit, and see what that dose.