Before I take it in...

rowar64 · #1 (**permalink**) 07-28-2009, 01:14 AM

Apologize for length...want to give history leading up to the problem. Hope someone can point me in a direction..

98 m3...cai is only mod...when starting up I am getting a really high pitch whine noise from front....picks up when hitting throttle then dies down. Lasts about 3 minutes and not always consistent. Can post video if needed.

Problem started about 5 days ago. OE underpanel broke on passenger side dropping down to ground, forcing drive side up slightly. Noticed it and "fixed" the passenger side. Same day I noticed the noise I fixed it ( underpanel ). I figured the panel had been rubbing up against something. Noise went away but 2 days later when driving off to work heard grinding coming from underneath. Underpanel had come off almost completely. Went back home and pulled it off and sure enough there was a nice circular groove on the baffle on the drivers side. Right below the alternator. (not noticing any electrical issues, btw). Ordered MM underpanel that night.

This weekend did a coolant overhaul, less swapping radiator...new thermostat, new t-stat housing, water pump, belts and flush. When I pulled the fan and cleaned it I noticed a large build up of plastic shavings...duh.

I can't nail down the exact location of the whining noise...it's not the alternator and more towards the center, possibly the fan....

Thinking now the plastic shavings that were worn off have gotten into parts and....ugh.

Thoughts?

99MPower · #2 (**permalink**) 07-28-2009, 01:57 AM

whatever it is, doesnt sound good...

bimmertuner · #3 (**permalink**) 07-28-2009, 07:13 AM

sound like the steering pump. Does the noise change pitch when you turn the wheel? I was getting a whining noise from the steering system so I immediatelly did a dlush and replaced the fluid and the noise stopped. Your sounds like it is more developed already.

BadGTho · #4 (**permalink**) 07-28-2009, 07:20 AM

thinking the fan is hitting the shroud.

take the fan off.. run the engine.. see if the noise persists.

KnudsonM3 · #5 (**permalink**) 07-28-2009, 12:00 PM

Quote:

Originally Posted by BadGTho

thinking the fan is hitting the shroud.

take the fan off.. run the engine.. see if the noise persists.

another reason to fan delete

BadGTho · #6 (**permalink**) 07-28-2009, 01:50 PM

Quote:

Originally Posted by KnudsonM3

another reason to fan delete

...to avoid fixing a problem?

99MPower · #7 (**permalink**) 07-28-2009, 03:13 PM

: owned:

completely agree Ben.. must find/fix problem first

rowar64 · #8 (**permalink**) 07-29-2009, 01:49 AM

Thanks all...Ben I'm kinda inclined to agree with you.
Irritating not being able to exactly pinpoint the sound but searching it down this had come to mind as well...

Only thing that gets me on this is the lack of consistency...Once the car is warm it pretty much goes away....

99MPower · #9 (**permalink**) 07-29-2009, 04:53 AM

have you removed the fan yet to try and narrow down?

i read the other thread and you said you just replaced the water pump correct? so highly unlike it's the WP bearing

rowar64 · #10 (**permalink**) 07-29-2009, 05:31 AM

gonna do that today Calvin...work sucks.

Yep just replaced water pump.

I3MW · #11 (**permalink**) 07-29-2009, 09:27 AM

Quote:

Originally Posted by BadGTho

thinking the fan is hitting the shroud.

take the fan off.. run the engine.. see if the noise persists.

+1 That's what I was thinking, leading me to think that maybe his motor mounts are toast.

It does sound like power steering noises but I don't think thats it from the symptoms. Also IME the alternator can still whine and work fine, but check the fan first as this can become a larger problem if left unfixed.

rowar64 · #12 (**permalink**) 08-02-2009, 01:37 PM

Finally got the time I needed....

Removed fan and whine is still there.
Noticed yesterday that steering wheel is now starting to vibrate in conjunction with whine...vibrates during whine (slightly but noticeable) and stops when whine does.....

power steering pump I am thinking

I3MW · #13 (**permalink**) 08-02-2009, 02:48 PM

Quote:

Originally Posted by rowar64

Finally got the time I needed....

Removed fan and whine is still there.
Noticed yesterday that steering wheel is now starting to vibrate in conjunction with whine...vibrates during whine (slightly but noticeable) and stops when whine does.....

power steering pump I am thinking

When you turn the wheel do you hear it and/or does it get worse. Is it whining kind of like an RC car?

rowar64 · #14 (**permalink**) 08-02-2009, 03:29 PM

Noise still continues when I turn the wheel, does not get any worse or intense.

Like an RC car is a very good description!

It's not constant and increases in pitch as I open the throttle.

The noise will stop within about 5 minutes when things start to warm up....

mikem · #15 (**permalink**) 08-02-2009, 03:51 PM

My underpanel failed and hit my AC compressor and ruined the pulley bearings. If the underpanel hit the PS pump while it was running, it isn't outside the realm of possibility that it was damaged in some way. If you take the belt off and spin it by hand (while cold), does it turn freely? Or are there places in the rotation where it becomes difficult to turn? Not sure on the RC car noise, but could also be belt slippage and/or bad belt tensioner springs/pulley bearings.