I'm stumped. Please help!
 

I drive a 93 M6 Z28. A couple weeks ago I noticed a little misfire but didn't think to much of it. As the days went be the miss got worse and worse. I finally pinned down exactly when it does it. Anywhere between 2,000-3,000rpm at anything but full throttle. If it starts missing I just floor it and it goes away even at a low rpm. Even if I keep it part throttle it clears up above 3,000rpm. The car pulls fine up top. It does not do it at all when the car is cold, only when I have been driving for about 15min. I replaced the Opti, plugs, wires, tried a diffrente coil, and hooked it up to a laptop. Everything looked fine but the long term fuel trims were not changing much, they were just staying right around 108. Any ideas?

If you are running stock fuel injectors, ohm check them. It sounds like maybe an injector is loosing resistance, and spraying too much fuel.

fuel filter

take the injectors off and clean them too.

put brake fluid in each one (one at a time)
hook a battery put to it
spray compressed air through it pushing the brake fluid out.

Fuel filter is only like 6,000 miles old. I was thinking injectors so I will deffinatly try that. Thanks!