Vibration through steering wheel at certain revs

[Corb2000]

Here’s a tricky one – my 3.0 multitronic is smooth as anything except for a strange coarseness / vibration through the steering wheel which happens when accelerating through 1800 and 2100 rpm in auto mode or in numbers 2 to 6 of the manual ‘gears’, (don’t feel it in first for some reason).

It is also present, although much less noticeable, when decelerating through the same rev band. It is also more noticeable when holding the bottom of the steering wheel.

I have 18” wheels with 235/40 Pirelli P Zero and Michelin Pilot tyres and did put the vibration down to poor absorption of road surfaces for a while but after much trial and error have isolated the feeling to these revs rather than speed or anything that’s happening on the road. It does not seem to make any difference whether the wheels are straight or turned.

My car’s done 47k and has the multitronic oil changed in the last 2k. Is this coarseness / vibration yet another multitronic quirk or could it be something else? Advice please!

 

[BahnStormer77]

What age?

Is it the 6 or 7 plate clutch version?

I know a lot of these were recalled (ALL the 2.5TDi versions) due to the multitronic's problems with higher torque levels.

 

[Corb2000]

It is an early car, 2002 on a 52 plate, and I've no evidence in the paperwork of the clutch being changed to the later 7 plate version.

The clutch seems an obvious suspect but I thought it might be something else given the vibration is at a specific rev range and there are none of the other symptons people describe on faulty multitronics - eg juddering.

The flywheel was suggested but there is no vibration at all when the car is in park / neutral, so that leads back to the drivetrain.

 

[quattrojames]

I don't know about petrol A4's but diesel A4's have one engine mount which electronically stiffens up at speed, and softens at lower speeds to absorb some harshness out of the engine. Worth checking maybe? If it has failed then some of this harshness may transfer to the steering column. I think a VAG-com scan will pick them up.

 

[Corb2000]

Thanks, interesting idea, I had wondered about engine mounts but did not realise they were more than blocks of rubber.

I can live with it for now so will get a scan done when its next in for any work, unless the problem gets worse in the meantime.

 

[Corb2000]

This steering wheel vibration was overtaken at the weekend by a serious vibration through the floor and pedals. Car was fine in neutral and I felt just a little vibration through the gearstick when it was in drive or reverse. However, the whole thing went pete tong when giving it some gas, especially going up hills, (coasting down the other side was ok).

The vibration got so bad we called out breakdown rescue, who reckoned it could be the diff. The steering wheel vibration did not seem to get any worse but hard to tell when you're being shaken through the floor as well.

Car booked in to my local independent this Thursday for a look see, they were busy until then.

 

[Corb2000]

Car now on its way to the famous Inde-Tech in Milton Keynes, again they're busy but expect to have a diagnosis by the middle of the week.

Not only has our A4 eaten its gearbox, my son's Alfa 147 manual refuses to engage 4th and we're told it needs a recon box as well, so avoiding the infamous Alfa selespeed in favour of a manual hasn't done us much good there.

 

[Solani]

What was the diagnosis?

 

[Corb2000]

This vibration seems to be beyond anybody to sort out.
1. Took it first to my local independent, Auto Logic in Harrogate, they said it was a transmission problem and take it to a gearbox specialist.
2. Took it to Inde Tech in Milton Keynes as they fix multitronics and they said my 18" replica wheels were out of shape so I replaced them with a set of original 17".
3. Took it lastly to York Audi which coincided with a coil pack failing, they replaced the coil pack but did not cure the vibration! Taking it back to them later today....

Car vibrates through the floor at anything between 40 and 70 mph BUT ONLY WHEN YOU PRESS THE ACCELARATOR PEDAL. It rolls along on the overrun quite happily, then you press the pedal and the vbration / shudder starts again. It's an absolute pain and makes the car pretty useless for any journeys out of town. This has been going on for 2 months and I'm ready to scream!!!

 

[Solani]

Have you checked your ARB Bushes?.....If they have moved can imagine that they would cause serious vibration.

Also....might be worth giving the sped sensors a clean.