[93hatchbake]

So I recently rebuilt my z6 in my eg. I reamed and honed cylinders. New piston rings rod bearing and main bearings. One rod was bent so I replaced it. Also valves were bent so I replaced them and seated them. Polished the crank. Ive got all new seals and replaced the clutch set. Everything is hooked up back the way it was and the timing is set right. But I still seem to have a miss. When its around 1000rpm it settles down. Seems like a vac hose is off but its all connected. Im getting healthy spark on all cylinders. No smoke out the back. When I rev the engine to about 3000+ I can hear a humming. I did clean everything thoroughly so maybe a sensor went bad. Only cel I have is for rear o2 sen which it doesnt have one so thats understandable. Please help me figure out what is wrong!

 

[jvtec8k]

My car does that humming sounds as well specially at idle. Does it affect how the car runs? If not, don't trip about it to much.. Im running high boost now with that humming with no problem but, I'm thinking it is air that makes that when timing belt spins. Again, i could be wrong

 

[93hatchbake]

Dont know if thats affecting it at idle. Just wasnt makin the noise before. Hopin somethin I put into it is supposed to make that noise at first. It is rough at idle though. Didnt know if I should drive it like that.