I have a 1985 22RE. Put in a rebuilt short block and new EB head and cam about 1300 miles ago. Engine starts and runs great when it is cold; starts idling rough as it warms up and gets much worse when it is hot.

I have checked for vacuum leaks, misrouted hoses, egr, timing and adjusted valves. I have found two things that might be contributing to it. One, when I put the timing light on #3 & #4 cylinder I see a miss sometimes. The other thing is when I did a compression check, I got the following.

#1= 135
#2= 120
#3= 125
#4= 118

Squirting oil into the cylinders only raised it about 7 psi.
I know these figures are way low, but how long does it take for the rings to seat? Any other ideas or suggestions as to what I can check or is causing the bad idle?
Thanks.

You need to get that sucker out and run the pi$$ out of it, ASAP!

Gotta seat those rings someday...

Sounds like a vacuum leak. A good way to find a leak in the intake system is to spray carb cleaner over your intake hoses and manifold gaskets with the engine idling. The EGR valve is a prime suspect, too. A speck of carbon inside can keep it from seating, and cause a hard to find vacuum leak. Best way to eliminate the EGR as a possibility is to unbolt it from the head, slip a blank gasket behind it, and bolt it back up.

As for the compression readings, do you have a National Institute of Standards and Technology certificate for that gauge? I get two different readings from my two gauges and learned a long time ago to not worry about what the absolute numbers are, but to worry when I see one number very different from the others. And even then, just removing the plugs to do the check can dislodge a piece of carbon which can hold a valve open slightly temporarily. So, don't jump to too many conclusions based on a compression check.

I have been driving the pi$$ out of it and will do some more when I get this idle problem cleared up. I will borrow another pressure gauge just to check out how close mine is.

I have sprayed all around the hoses and gaskets and nothing shows up. I will try blocking off the EGR and see if that helps.

Can you tell what the missing that is shown by the means?
Thanks for the replies.