Been looking around forums but cannot find a definitive answer. Anyone know what this noise could possibly be:

http://www.flickr.com/photos/78132349@N08/7214032818

I can really only hear the noise at lower rpm 1k to 3.5k maybe. Also it occurs when revving the engine in neutral and stopped. Sounds like it is a belt of some sort but not sure what normally fails with an Evo 8. I read that it may be the serpentine belt or A/C pulley going bad that causes this problem. Is it possible to change A/C pulley?

My car is a 2004 Evo 8.
Thanks in advance.

 

That is weird, I'm curious what it could be also. Free bump

 

Also curious as to what this is...I've definitely heard that same noise in my car, I always forgot to track it down whenever I stopped. It's not there all the time, just every few days I'll notice it..some times it will show up after starting the car back up after stopping briefly like for gas or something.

If yours does that all the time, just get your head in the engine bay and track down where its coming from...maybe you would want to get in there with a stethoscope if you have one (I have one in my garage for some reason haha)

 

Sounds like it could be your alternator accessory tensioner pulley. Not positive but sounds very familiar.

I found a thread on here, EvoM, with someone else who had a VERY similar engine whine..(myself included). They ended up throwing a bunch of parts at it and it turned out to be the alternator accessory tensioner. I'll see if I can find the thread and post the link here.

I have the same whine but have yet to replace the part I'm referring to so I am unable to confirm this is indeed the culprit.

STM sells this part for $141 LINK

I'm very interested to know if this solves the whine.

Keep us posted!

 

Did you just recently change your belts? My car made this same noise, my timing belt was to tight. If you didn't change your belts I thinks it's the hydraulic tensioner.

 

The car only has 10k miles so belts are still factory. I think your right about the alternator accessory tensioner. I went under the car since I can hear noise much more under car. It seems to come from an alternator looking device at bottom of accessory belt area. I will take a pic and highlight area.

 

My car had a similar noise. It wound up being the large idler pulley. You need to run it and listen to each pulley with a stethoscope.

 

Any news on the fix?

 

Take off the accessory belt and turn all the pulleys and see if you feel anything binding or with play or feel anyway it shouldn't feel. If not then could start it and if the sound is still there then you know its timing belt related and not the power steering or alternator or anything on the accessory belt system.....Obviously don't run it too long since the battery won't be getting a charge

 

Bringing back this thread, since I will be working on this tomorrow. Will give updates.

 

Not commenting to help about the problem sorry, but gawd dam 10k miles on an 04 evo 8! Lol

 

I have the same noise, I have eliminated everything (Changed timing belt 3 times, tensioned several ways,now at factory spec, changed ALL pulleys and Acc belt twice) and I believe its the alternator. The noise is in that area and its the absolute only belt drive item I haven't changed.

 

Took the serpentine belt off and the really annoying whining noise is now gone when I rev the motor. It use to be worst at 3k RPM. I will replace the serpentine belt (due for change since 11 years old and cracks) and the tensioner pulley since it had alot of side to side play. All the other pulleys did not have much play or make noise. Will let you know how the new parts go. I was going to order the Gates tensioner pulley (Part # 36238) as referenced from Rock Auto for my 2004 Evo. Ordering the Goodyear belt 4060705 Poly-V Belt. I hope the pulley is the correct one but everyone is saying to reference RockAuto.

 

The car has 35k now, but bought it with 7k. The original owner never drove it and got a DUI later which made insurance too much to buy.

 

I bought an accessory belt tensioner pulley from Advance Auto at a huge discount to anywhere else I could find it - about $50 as I remember. The Advance Auto part is identical to OEM except the makers name is ground off.