Guys,
it's time once again for another not-so-easy-problem for me to trace. My Silvy has 170,000 now and is mostly stock except for K&N and a Corsa catback.

A few days ago I put a new idler pulley on as well as serpentine and A/C belts. The next day I develop a whining-ish type noise. The alt is still charging correctly, no fluids are leaking and nothing is low.

Tonight I got some in cab audio and if you listen you can hear it. It doesn't change with rpm but only shows itself between 800 - 2,000 rpm and 10 - 20mph. It only does it when being driven and I can't duplicate it in park. When the revs are coming back down, it doesn't seem to follow. What I've done to check this is to take it out of gear when it starts so the revs will drop and the noise stays. I don't hear any metallic grinding or any other noise. No other driveability seems to be affected.

Any ideas?

 

bumps in the night

 

Check your ground wire for you audio system. Check if it is properly grounded and if the wire matches gage specs. If not that it could be your power wire is to close to your engine causing a disterbance in the signal going to your deck,amp,speaker,etc. I had the same problem and ran the power wire over the fender and across the firewall. If it is a costum install take it back in and adress the problem.

 

It's not feedback through the stereo. It's coming from the front end somewhere.

It has gotten warmer by about 20 degrees in the last few days and has apparently gone away for now.

Time will tell and I've got the rest of the week off to figure out what it might be.

 

Mine has the same noise. I thought it was the power steering pump at first... but it sounded the same before and after I changed it.

almost sounds like a low volume blower right?

 

Wheel bearings???

 

if its the same as mine, it does it idling sitting still... I dont hear mine at low speeds though... only sitting still at idle. Its not loud, or annoying, you can just notice it. My fans cover up most of the noise anyway.

 

Hmm sounds like the same noise on my truck. Wheal bearings you say. For me it gos on and off but once truck is wormed up it goes away. Comming from the front drivers side it really is annoying and sounds like its comming from engine. Kinda sounds like a bad idle pully but I checkes that. Going to take it in to a shop soon to do ball joints and alignment Il have my buddy take a look.
Il keep you posted.

 

what brand belts are you using? some brands are very noisy.

 

It's not the engine. I would say transmission. There might be a crack in the hub of the sun shell causing it to wobble and move relative to the reverse input shell.

If it's 4WD drop the transfer case into neutral in motion and see what happens.