I start my car in the morning and at idle, I hear this low humming noise coming from the engine. So I change all my belts. Still the same noise. It only last for about 5 seconds or less. It sounds mechanical though. It only happens once a day at mornings or if car hasn't been started up for a while.
Ive search in here and no one has the same problem. I know what air intake sounds like. And its not the wheel bearings cause I'm not rolling.
This might help: All I have are 421 dc headers k&n short ram and 2 1/4 custom exhaust SPP. and 8 mm magnacor spark wires. ngk spark plugs. Everything else is stock.
Can someone help me out and give me your input? Thanks.