High pitched engine noise

[Spaceman Spiff]

Last week I noticed a slight high pitched whistle-like element in the engine noise everytime I pushed the gas pedal. It is barely audible but since I noticed it and listen for it, I can hear it every time now. Any idea what this can be?

[MinneapolisJeff]

been dealing with such a problem since i've had mine it can be caused by a variety of things as I've found out...search the forum and see for ya self

few areas to check:
1) air intake boot; look for cracks in the hose - wasn't an issue on mine
2) serpentine belt slippage - changed both of mine
3) mechanical belt tensioner gone bad - on my TODO list over Labor Day weekend

I also had a bad pulley on my engine (bearings) and replaced that as well

[Spaceman Spiff]

Thanks! Heading over to REALOEM to identify all those parts Was it all DIY or did you have the dealer take care of it?

[koj415]

I've had a similar problem, but notice it mostly at idle. Started off-and-on but now it's pretty consistent. Dealer denies hearing it at all...

If you find out, please update this thread!

[enlightenment]

Did it go Woooh Woooooh? I think i found your problem...

Don't worry. "It's just for decoration man. It's just for decoration... That's it and that's all man..."

[pingpong]

I had this same problem. Mine is really only noticeable when I gas it between 2-3k rpms. Took it to the dealership to diagnose; tech said it wasn't anything to worry about. I'm not convinced though...

[MinneapolisJeff]

Originally Posted by Spaceman Spiff

Thanks! Heading over to REALOEM to identify all those parts Was it all DIY or did you have the dealer take care of it?

DIY on everything, don't feel like spending money on these types of maintenance items. Since this is a summer-only car, I felt like I could be more involved on little issues, but will leave the big ones to a mechanic.

That being said, fixing this type of noise wasn't even really an issue, more like an annoyance. I didn't like having a screech/whistle coming from the engine when I left an intersection w/ lots of ppl around LOL

[Rabid Panda]

So what is the verdict? Anyone track it down?

[MinneapolisJeff]

Originally Posted by Rabid Panda

So what is the verdict? Anyone track it down?

my issue was tensioner + serpentine belt, no more sound after they were changed

[johanness]

Now u gotta watch for deers

[santov]

Originally Posted by jman1975

my issue was tensioner + serpentine belt, no more sound after they were changed

Just for future reference: Was it the tensioner itself, or just the pully/bearing? There's a big price difference between the two. How many miles did you have when it started to make noise?

[Rabid Panda]

I replaced both tensioners and the belts.. still does it.. thinking its the idler pulley on the alternator.

[Spaceman Spiff]

Mine was a rip in the air intake boot. Replaced the intake and it went away.

[MinneapolisJeff]

Originally Posted by santov

Just for future reference: Was it the tensioner itself, or just the pully/bearing? There's a big price difference between the two. How many miles did you have when it started to make noise?

The noise was there from the start for me, bought the car used w/ 37,xxx miles on it

Pulling on water pump belt with my hand would make a squeak and I narrowed down the sound to the mechanical tensioner. So when I replaced the tensioner, I just replaced both belts while I was at it. BTW, the mechanical tensioner was no longer available from BMW, only hydrolic, had to get an aftermarket one

[Jax543210]

Originally Posted by Spaceman Spiff

Mine was a rip in the air intake boot. Replaced the intake and it went away.

I've checked my air intake piping pretty closely, but can't find any damage. That noise I'm hearing is very annoying. I'm still hopeful it's something simple like the air intake. Can you describe exactly which piece of your air intake was damaged. Maybe it's the same for me. Was it the rubber sleeve that connects the air box to the intake at the front bumper or was it one the the pipes/boots after the air box that run to the engine?

[Jax543210]

Originally Posted by pingpong

I had this same problem. Mine is really only noticeable when I gas it between 2-3k rpms. Took it to the dealership to diagnose; tech said it wasn't anything to worry about. I'm not convinced though...

Were you ever able to get the noise to go away? I have a similar problem in that RPM range.

[Rabid Panda]

I changed the belts, the belt tensioners, and the idler pulley on the alternator..., and it still makes that ridiculous noise.. sounds like a swing set on a play ground...(that's what the wife says). Will change the entire intake hose system next, will see if that makes it go away.