Am I missing anything? Compression issue

[Dutchinohio]

OK to review.... 1999 P71 with 160,000 (4.6L)

Compression test results are dry/wet...

1) 130
2) 110/130
3)130
4)110/125
5)110/125
6)130
7)110/125
8) 0/0

We pulled the valve cover yesterday. I found no problems with followers, lash adjusters or springs. I assume a valve needs to be burned, piston holed or gasket blown. I see no evidence of the head gasket being bad. #7 is ok, no coolant loss or leak and no external evidence noted of a problem.

Is there ANYTHING else to check that doesn't involve pulling the head? This is about as deep as I want to go on this car. If I can't fix it without tearing it apart too much farther we'll problably just sell it. Too bad... it's a darn clean car.....

[MagicRat]

Check for blow-by. Remove the oil filler cap when the engine is running. If a piston has a hole, it will chuff air out the oil filler like a steam engine.

If there is no blow-by, hook a vacuum gauge up to the intake manifold when the engine is idling. Normally the needle should hold steady at 18-20 inches. A leaking intake valve will cause the needle to bounce regularly.