srs bzns

iTrader: (3)

I have searched and searched and read every related thread I could have possibly read and tried a few things that I thought might be the issues and still have not found the fix for this.

At idle and only at idle I have this absolutely deafening "dog whistle" noise emanating from my engine bay when the HVAC is in the off position. AS soon as the rev get above 1200 its gone, or as soon as you even just simply turn fan for the HVAC off it is gone. The second you turn the HVAC off it is immediately back, and can literally be heard for blocks. Now the is with heat or cold on, ac on or off, and i checked to see if it was just the HVAC raising the rpms enough to stop the sound and it is not

My heat blowers incredibly hot, my AC blows cold, blower motor seems strong. I have lubed pulleys and blets. I have replaced pcv hosing across top of the motor (the one that has the standard vacuum leak). Car has 104K miles on it, I have owned it for just about a year and had to replace a lot on it as it was neglected. Motor runs strong, no cels, no misfires. This noise has been here since i purchased it.

Other issues I am addressing but i do not think are related:
recent: coolant boils in reservoir and radiator AFTER car is turned off. Car never overheats, never moves over 210*. Fans operational, coolant and oil appear clean. (I believe this is the radiator cap, waiting for OEM to get here in the mail...today actually.)

Since purchase: On hot days after long use the can makes the standard power steering pump low on fluid sound while driving however the reservoir is full and system has no leaks, no bubbles in the fluid

I'm completely at a loss on this noise. Like i said it is deafening and somehow HVAC related, it seems to be coming from front passengers side of the engine bay. I do not think it is AIR because its constant, hot or cold. AIR would generally just be cold start correct?

LLLosingit

iTrader: (4)

It's common for the ac compressor clutch to hang and not fully release and make noise until you turn the ac back on engaging the compressor clutch. Is it a metallic sound or an actually whistle?

srs bzns

iTrader: (3)

It could possibly be extremely high pitched metallic sound, but it does seem to definitely be more of a high pitched sound like that emanating from a dog whistle if you can hear it.

I listened to a number of ac pulley videos and none of them sounded remotely similar

srs bzns

iTrader: (3)

This is accurate to the sound but 10x louder

hrcslam

I think it's time to pull out the stethoscope. You need to pine point the origin before you can go any further me thinks.

Infantrymarine

iTrader: (3)

Sounds like an idler pulley noise to me.

Firebrian

I expected a lot more noise on the video. Not even sure I can hear the problem noise.

If you've never done anything with the power steering fluid I would at least change that out. It may not help with the noise but it will be better for the system to have fluid that hasn't been potentially overheated recently. At $8/qt for the GM stuff I change out 32 fl oz from the reservoir every 1-2 years.

I wouldn't trust the factory temp sensor. A better bet would be to use an infra red gun on your cooling system.

wssix99

iTrader: (5)

^ This. Go spend $10 on a mechanic's stethoscope before you spend hundreds on parts, guessing.


You just have a bad bearing somewhere that quiets down when the engine is under load.

srs bzns

iTrader: (3)

The sounds doesn't translate well to cell phone microphone. I did make some head way on the noise this weekend.

It is definitely HVAC related, and I am almost sure related to the AC compressor and to top that off I think that is related to my over heating.

I pulled the AC belt and the noise was gone and the car idled so much better. 8-900 rpms nice smooth idle.

I lubed the tensioner and put the belt back on same noise and same 1100 rpmish idle. I crawled under the car and the pulley on the ac compressor is a bear to spin. Thinking it must be seizing for some reason.

Anyway I left the belt off, swapped my radiator cap and car runs great now in fact not power steering whine yesterday and it was about 92* outside

Darth_V8r

iTrader: (4)

It could absolutely cause the overheating. It's a drag on your engine. Like having a stuck caliper.

srs bzns

iTrader: (3)

yeah, the car has been running great now minus the ac belt, and the weather has been incredibly hot and humid

1 FMF

iTrader: (1)

15mm wrench remove the main serpentine belt and then start engine and idle and see if noise is still there. if so undo the ac belt and check again. this will rule out anything on front of motor minus the crank pulley.
or you can manipulate the tensioner pulley with the wrench while engine is idling and see if it affects the noise, but don't lose your hand.

eseibel67

iTrader: (10)

Check your PCV valve. I changed to one of those valves that use a fixed orifice instead of a spring valve and it sounded just like that. Changed back to a regular PCV valve and all was good.