Every now and then I get a weird loud "whining" sound coming form the engine if I "lug" the engine around at 2-3k, it's very loud and very distinct. Kinda sounds like a cross between a jet engine on takeoff and the normal whistling that comes from the turbos (it's not the BOV, I know what that sounds like, this is about 10x louder). Either taking your foot off the gas or gunning the gas stops the sound. The sound comes and goes (the car has gone for months without the sound, only to have it return for the next week straight), but only occurs if I'm "lugging" the car around (not in boost) between 2-3k rpm. I've had the sound since I bought the car 3 years and 27k miles ago. When I first bought the car, I thought it might have been the turbos, but I've had no loss of repsonse or boost in the last 3 years. If it isn't the turbos, anybody have any idea what it is?

 

Likely your CRV venting. It's normal but I've never heard it whistle.

 

Maybe the throwout bearing or pilot bearing on the clutch assembly could make a whining noise during those RPM's. Transmission bearing? Is the transmission really warm after a long drive? How old is your clutch?

 

If you still have an airpump, pull the plug going to it's clutch an see if the sound goes away. If it does, it's either the airpump on the ACV.

 

Is the plug to the clutch the grey connector going to the front of the air pump?

Thanks!

 

Yep, It's the one located on top of the airpump. It's easily (for an FD) accessible. Warning: don't run too long (ecsp pulling boost) without the airpump or your main cat will end up spayed.