IslandS52

2006 Carerra S, 75k miles, 6 speed.

Noise just started today on the way home. Car is running normally but has a loud squeal, which seems to emanate from the right side just behind the rear wheel. No obvious fluid leaks. Shutting off the AC compressor does not seem to stop the noise, and it seems to be related to the engine fan. Is there a fan or bearing in that location? anyone have this problem before? I'll try to look more closely tomorrow but my dealer can't look at the car until Jan 3. Any diagnosis help is appreciated.

IslandS52

the noise seems to be coming from the area labelled #5 in the photo above, which I understand normally to be the AC compressor. However, the ECO button does not seem to stop the screech.

Spokane5150

Could be a pulley or your water pump.

997_rich

after pressing the eco button you wait a few seconds, right?

for starters, I'd use a 24mmm socket on #7 above and push down to remove the belt.

I'd examine the belt for glazing or cracks (if it's got more than 30k just replace it), then spin each pulley and make sure it doesn't squeak or joystick or have endplay.

also double check to make sure you have power steering fluid and make sure the ac blows cold.

is the squealing a belt type squealing? consistent? pulsing- how often, with each rotation of the belt or each rotation of pulley? does it sound like metal on metal? does it sound like old roller skate wheels?

okbarnett

Could have got a squirl up in the engine. ?

IslandS52

I am pulling the belt and inspecting the pulleys today. I only have about 3 minutes of actually hearing the noise while driving so I can't pinpoint a pattern quite yet, just that it's loud and not normal!

irish guitar

Have you replaced your water pump? My '06 needed one before 30k miles. The noise you describe seems similar to what I heard right before it all went pear-shaped...

IslandS52

I have a water pump spare ready to go, but I still have the original I'm the car. thanks for the warning.

I inspected the car this morning. No fluid on the floor, a good sign. I removed and inspected the belt and checked the tensioner and pulleys for noise and play and came up empty. I warmed the car up and drove to get it to operating temps and no noises. something was up yesterday though, no use trying to ignore it.

I'll drive the car with caution and take it to the dealer next week and have it inspected.

IslandS52

diagnosed as air/oil separators by the dealer. the check engine light lit up on the way there this morning. $1400.

txhokie4life

$1400 Dang, AOS is $100 part. maybe 3-4 hours of labor .

Buy my ticket and I'll fly to Hawaii :-) Still have to be cheaper than $1400.

Mike

IslandS52

I figured it to be high, although they are claiming to change several hoses and other parts that look suspect/brittle.

Dadio

You may need all the stuff the dealer suggests but not sure how thats going to fix the screeching sound. Let us know if it goes away after the repairs are complete. Bad pully bearing and/or belt slipping sounds more likely to me.

IslandS52

I went back and read some threads on AOS and a few do indeed mention loud squealing. I am not familiar enough with them to really know why they present that way. afaik BMWs never had them!

vexed

Ouch. Sorry to hear it is the AOS.

911ct

There is a nice DIY for AOS change on Renntech for the 997.1 C2 S. Take a look, maybe you decide to do it yourself.