I recently had a valve job done on my 91 240SX. The engine ran OK before except for a tendency to die at idle. I went to change the plugs and discovered a stripped sparkplug hole. Since I had to remove the head to have that repaired, I thought I'd get a valve job at the same time. Upon reassembly the car ran poorly and had little power. I did a compression check today and had 90 psi on all cylinders. I rechecked my cam timing and it is just as the service manual outlines. What is going on? Could an incorrect valve job cause low compression? Did the rings go bad while the head was off?

HELP!!

First off, why do you have a 98 neon??? jk Anyways, I would doubt it was your rings, unless they left it outside with the hood up when it rained "very. . . very doubtful" and that would lead me to suspect it was the valves. Before you got all that work done to it and you stated it would die at idle. Did the idle speed fluctuate at all before it died. If so I would suspect the ecu. Thats just my 2 cents though. Goodluck though.

I just checked the valve clearances. I checked them cold and the specs are for hot. 6 out of 16 were too tight by .001 to .003 inches. When hot would they be looser or tighter? I think they would be looser and therefor OK but I'm not sure.

I would have to disagree with you there my friend, "even though I am unexperienced". When metal gets hot it expands therefore I think it would be tighter.