chirping when first releasing clutch in reverse. - United Bimmer Community

**mcormg1** · 07-05-2012, 10:30 AM

Hi. this is my first question after just buying a sweet 98 323 convertible. When I start out in the morning by backing out of my driveway, I hear a chirping kind of sound when letting the clutch out. It only happens for a second and then I never seem to hear it again for the rest of the day nor in first gear. Just reverse when cold. Any ideas? I thought perhaps a throwout bearing but would expect that to make more noise in more gears. Also the clutch was replaced by previous owner 25K kms ago so assume they woudl have changed the throwout too. Thanks folks

**Manolito** · 07-06-2012, 08:08 AM

Just a single, quick chirp? If so, I would suspect that the parking brake is not releasing until the rotor starts to turn backwards. Another possibility would be a control arm or rear axle assembly bushing.

Or is it a recurring chirping sound that makes multiple sounds and goes on for a second or two?

**mcormg1** · 07-06-2012, 07:10 PM

Quote:

Originally Posted by Manolito

Just a single, quick chirp? If so, I would suspect that the parking brake is not releasing until the rotor starts to turn backwards. Another possibility would be a control arm or rear axle assembly bushing.

Or is it a recurring chirping sound that makes multiple sounds and goes on for a second or two?

thanks for the reply. it seems to be single incident of one or two chirps perhaps a second long and so far only in reverse. once it's warmed up i dont notice it again in reverse. i thought perhaps a throwout bearing but your parking brake idea is interesting. i rarely use it though so would that still be a possibility?

**Manolito** · 07-08-2012, 08:37 AM

The parking brake would be a good theory only if you had set the parking brake when you stopped.

The throwout bearing does not know whether you are starting out in forward or reverse. However, the transmission mounts, guibo, rear axle assembly bushings, rear shock mounts, and even the engine mounts all shift the opposite direction when you start out in reverse. We have a long list of suspects here. Fortunately, the problem is not urgent so you can wait until it develops into a clunk and is easier to find.

If this were an early e46, my first suspect would have been the dreaded cracked body around the rear shock mounts.

**mcormg1** · 07-10-2012, 05:16 PM

Now that I'm listening for the noise I can hear it first time starting i the morning and doesn't have to be when shifting into reverse or first although that is when i hear it most.
It doesn't happen again through the day when the car is warmed up.
it's like a loose bearing or idler chirping somewhere low and seemingly from the left side. Only there for the first half minute of so then goes away till I start it up again in the morning. it seems to be getting somewhat more pronounced or worse so would really like to catch it before it gets too bad or something fails.
thanks

**Manolito** · 08-05-2012, 10:41 AM

A speed dependent repeating sound that happens for the first few blocks and then goes away for the rest of the day is usually a wheel bearing. This noise most often makes it into the cabin as a whomp, whomp, whomp sound, but can also chirp or squeek.

These wheel bearings are notoriously difficult to remove. I wasted a can of propane and broke two pullers on my e36 before I gave up and took it to a shop.

The odd thing about e26 rear wheel bearings is that they routinely fail at around 200k miles. The small Mercedes uses the same bearing, and they never fail. Must have something to do with heat dissipation (or maybe e36 owners just drive harder).

**Carmine-i** · 08-08-2012, 01:51 PM

If the noise is not dependent on the car moving, and only happens when it is cold I would turn on an accessory like the lights or AC in the morning as soon as you start. If the noise is worse, prolonged or even louder it is most likely an idler puller on the belt drive system. I had a similar problem and let it go until it became easier to trace. You can use a mechanics stethoscope and place it on the bracket of the idler pulley close to the pulley itself and listen for excessive bearing noise. They are not expensive and very easy to replace.

**mcormg1** · 08-10-2012, 05:24 PM

Quote:

Originally Posted by Carmine-i

If the noise is not dependent on the car moving, and only happens when it is cold I would turn on an accessory like the lights or AC in the morning as soon as you start. If the noise is worse, prolonged or even louder it is most likely an idler puller on the belt drive system. I had a similar problem and let it go until it became easier to trace. You can use a mechanics stethoscope and place it on the bracket of the idler pulley close to the pulley itself and listen for excessive bearing noise. They are not expensive and very easy to replace.

Thanks for the response. I tend to agree with you as it only happens at cold start in the morning and not usually the rest of they day (its been really hot here). Sounds like it's coming from that area. I'll try the stethoscope or a long screwdriver to pin point it.

**Carmine-i** · 08-21-2012, 06:16 AM

How did you make out?