PDA

View Full Version : Strange Nosie while driving...



BlkBullitt
02-27-2009, 07:52 AM
I've search several forums and haven't really found anything so here it goes...

First, my car is a 1998.5 B5 A4 2.8 Quattro 5-Speed with both the Sports Package and the Cold Weather Package. It had roughly 106,000 miles on it. The only modifications I've done to the car are the B6 A4 5 spoke sport wheels I've recently added with 235/45/17s with 8mm wheel spacers and longer ball seat lug bolts (otherwise the car is 100% stock).

I'm hearing what sounds like a combination of the noise a car makes when driving over a rumble strip on the side of the highway (but faster) and a rattle. It sounds like it's coming from the rear of the car. This only happens...

When I'm accelerating at about 60-80% throttle (so not full throttle, but not light acceleration), but only in 2nd gear (often... maybe 80% of the time the car will make the noise), and very very rarely in 1st gear. This usually only happens between 3,000 and 5,500 rpms in the gears mentioned above. The car doesn't do this in 3rd, 4th, or 5th.

As far as maintenance goes on the car...

1. I've replaced 2 wheel bearings (front passenger, rear driver) and am about to do the other two
2. I've replaced the TREs (with Meyle HDs)
3. Car was aligned about a year ago at my local Audi dealer (after the above was done)
4. I've had my ABS module refurbished
5. I replaced the coolant temperature sensor
6. I recently did the timing belt, water pump, thermostat, tensioner, swing arm, idler, front crank seal, and other front oil seal.

Oil gets changed every 5,000 miles with Mobile 1 Synthetic.

Any ideas?

Jibberific
02-27-2009, 08:05 AM
rear diff mount maybe?

JumboBlack1.8
02-27-2009, 08:25 AM
That sounds like a wheel bearing to me......my car made a similar sound about a year ago. Replaced the bearings....problem solved

BlkBullitt
02-27-2009, 08:38 AM
Really? I know bad wheel bearings make a humming sound that increases in volume with speed. I know I need to replace the rear passenger's side one (it's humming) and I'll have the parts this weekend.

Any other thoughts?

D's Avant
02-27-2009, 11:38 AM
Simular problem on my car right now too. I'm replacing the rear wheel bearings soon. Def jack the car up and check the diff mounts and CV joints too though.

BlkBullitt
03-16-2009, 06:57 AM
Well I replaced my two wheel bearings this weekend (this makes all 4 of them now) and also ended up replacing a front control arm (ball joint was bad).

All of the subframe bushings looked good and the car is still making the noise. Not as much as it was, but it still is.

Always in 2nd gear between 3,000-5,000 rpms when you give the car a good amount of throttle.