I have 0 compression in Cylinder 8. Put drops of oil in cylinder compression went up. Truck not blowing smoke but has rough idle Hesitates. Spark plug black but not wet. New coil. Getting fuel and spark. Anything I can do to get compression without tear down?

2002 4.6 4x4 164,000

Any help appreciated.
Lind

 

Not really. You can rotate the crank till that cylinder is at top dead center them plump an air line into the spark plug hole and blow air into the cylinder and see if it comes out the intake, exhaust or through the crankcase and that should tell you if you have a burnt intake or exhaust value or if the air is getting out through bad rings or a blown piston but in every case you're going to have to pull the head at a minimum so you may just skip the examination and go ahead and pull the head and then the problem will be obvious.

With 164,000 miles, I think you should consider a complete engine overhaul or replacement and not just a repair.