98' Corolla Cylinder 4 Misfire

We hooked my car up to a computer and found a cylinder 4 misfire. We systematically eliminated all of the obvious culprits; plugs, wires, coil, and fuel injectors. Any ideas? A valve problem?

" A valve problem?"

No need to guess. Just check the compression.

A wire that only misses 1 out of 10 or so times will cause a code.