High RPM misfire

[mx6gt1]

Hi
I have recently bought a 2005 X5 3.0i. When I bought it, it was smoking so i changed the cvv and all hoses. I have also replaced a bad DISA vavle, the O2 sensor, valve cover gasket, and battery. It finally runs great EXCEPT when it revs up to ~5500 rpm. The engine light comes on and it starts running rough, especially at lower RPM. Sounds like its running on 5 cylinders. Turn it off and start it and it runs fine again. The only code I get is misfire on cylinder 5. I tried changing the plugs around, then the coils, and it still misfires on cylinder 5. I did a compression test on 5 and 4 and they both came in at 150psi. I'm not sure what they should be at.

There is a bit of oil on the spark plug threads, but i figure it only has about 20km on it since the CVV was changed, so its probably remnants.

Any help is appreciated.