With all the great advice on this site, I'm hoping you guys can help me with this one. I have a 2000 SSEi with 76K miles on it. I am getting a "whiring" noise at highway speeds that is more pronounced when you are accelerating. If you let off the gas pedal the noise dissappears but reappears once the engine returns to load. It sounds like some kind of bearing that is going bad and I suspect the supercharger. There is no noise at idle or even when I rev the engine at idle. I have removed the belt to the supercharger and drove the car at highway speeds but still heard the noise. I thought it might be something other than the supercharger until I lifted the hood and manually reved the engine. Without the belt on it, the supercharger was still turning driven by the manifold pressure. I also noticed that without the drive belt on it, the supercharger was slinging oil out of the pulley. But when I put the belt back on and run the vehicle, no oil is lost. I don't want to replace the supercharger with a rebuilt one if that isn't the problem but I am perplexed at this point. Also, looking at the task of removing and replacing the supercharger, it appears it is a big job since you have to remove the fuel rail and possibly the injectors to do it. Any advice or other diagnostics I could do to confirm the problem? Also, are there any step by step instructions on removing and replacing the supercharger without buying the full shop manual? Thanks in advance for your advice. This shade tree lightweight mechanic needs all the help he can get. Plus, this is my wife'* car and I need to eliminate any nag factors.!

Seems to me you are on the right track. If the SC is just free-wheeling, seems to me you could use some good 'ol duct tape and shut the spinning down while you check for noise.

If this is done, the engine will have no air. Please don't do this.

If you still get the noise. Please remove both belts and freewheel each pulley by hand. Feeling for any bad bearings. Also check the power steering fluid level. The pump can be noisy when low.

My bad.