Engine Noise W/Video Sounds like a supercharger
 

OK Guys.

Need some help here. Just got my car back from the indy and made several repairs. The engine noise started a few days ago and I took it right in to my local Indy. 2002 4.6 with 73,000.

First thought was a intake manifold cover in the rear, I think it is also known as the oil separator. replaced.

Noise still there.

Next replace both belt tensioners. Indy said noise was coming from only one, but recommend to do both at the same time. Done.

During this repair he found the water pump to be leaking, fine replaced it and all the belts. Thermostat too.

Get the X back and the same noise except its even louder. So I am not happy after shelling out over $1,700 for all this and still have the noise. They will start looking it over again on Monday. Anybody got any suggestions on what this might be?

http://i255.photobucket.com/albums/h...h_P1000846.jpg

Could this not be engine related but rather something else in the drivetrain?

I watched a Top Gear video and one of their cars had a similar noise under acceleration and that was due to a shot flywheel bearing. I'm not suggesting that it is the flywheel bearing, but could it be any other bearings in the vehicle?

It sounds like your engine fan clutch is toast and is stuck on... My 2 cents. but it definitely could be a supercharger, haha

Since water pump and pulleys have been replaced I am thinking either fan clutch or alternator.

+ 1 on fan clutch

What about the other tensioner, on the AC belt? The easiest way to isolate if it is belt drivin or not is to just remove the belts then start it and rev a couple times to see if the noise is still there. I've heard alternators make that noise when the bearings in them were on the way out. I'd say the noise is definitely engine speed related vs road speed, and seems to be amplified under load... If it is the alternator, I feel your pain... that water cooled 180 amp sum-bitch costs a pretty penny.

in the old cars if that noise hapen , is definetly the carburator,,, it gets blocked from the dirt in the fuel,,. i dont know how is the power the torque compairing when the x didnt have the noise !!!?
if the power is not the same,than check the catalic converters the whole exoste line and the fuel enjection,,and change the spark plugs if you didnt,,.

Great, now it appears there is some oil leaking. not sure if its engine oil or gear oil. Its really black and thin. Oil was changed about 4,000 miles ago with royal purple. Jacked the X up and looked underneath. I looks as if it is leaking where the tranny and engine meet.

There now seems to be a rattling noise at idle, which turns into that high whine noise when throttle is applied.

There doesn't seem to be any loss in power.

Both tensioners were replaced.

Alternator or Aircon pulley / bearing had this sound on my Volvo S80, it came from the Air Con Compressor pulley