Hey guys, I'm wondering if anyone can help me diagnose a noise that suddenly appeared. It first came about 4 months back. It sounds like a turbo whistle that you can hear from the exhaust when it is spooling down. The car is a 2000 Impreza L with the original 2.0L motor and AT tranny and 75k miles. Its been in my family since new. I have done all the maintenance on it. There are no mods on the car.

At first, I thought it was the alternator going bad since that is where the sound was coming from. However, after changing the alternator, the sound still exists. Its been slowly getting louder and louder. The pitch of it changes as the rpms increase. I'm slowly beginning to think it is an idler pulley. I still need to do the timing belt, water pump, etc. Anyone have any clues on what it could be? I'd like to get to it while i'm doing the timing belt.

 

Try taking the belt off the AC. See if that pulley is the culprit.

 

Will do, i'll do that this weekend. Thanks for the suggestion.