A guy at work bought a 92 Isuzu Amigo.It has ran rough since he bought it.He had a shop look at it they said rings were bad 70 lbs. compression in no. 3 cylinder.A month later He asked me to look at it.It had 0 lbs in no.3 and it did not come up when I squirted some oil in the cylinder.All other cylinders seem OK.I thought a valve was bad. I put some compressed air in the cylinder and it would not build any pressure at all.He has a receit from 1999 from a dealer that replaced the valves in the no. 3 cylinder.Does anyone have any opinions what the problem could be?Exhaust valve burned? If so is this a common problem with the 2.6? Any suggestions on best possible fix? The guy does not want to put a lot of money into this.Thanks

on the #3 in a 2.6 it is very common for the head to crack around that one or the head gasket to blow around that same cylinder. the 2.6s are notorious for head problems. was it blowing any white smoke? antifreeze in oil? just somethings to look at.
good luck
Eric

2.6s are alos bad for burning exhaust valves if you don't keep up on the adjustment. that would be my guess with 0psi is a valve that's totally smoked.