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Brawn
22-02-2012, 12:37 AM
Two-pronged question, I'm afraid, and need answers to both.

Part 1
Bought the Jetta about 4 weeks ago (2006 '55' plate 2.0TDI PD Sport) and ever since I've had it there seems to be a whine coming from the front drivers side (30 and above and always a fairly constant volume). Took it back to the garage where it was bought to be investigated, which has ruled out bearing/drive shaft and is un-resolved.

Any thoughts?

Part 2
Visited a mechanic friend of mine today to see if he could get to the bottom of it (without taking it out or getting it up in the air, he also was unable to diagnose). But while talking to him, he pointed out the violent engine shudder on shut-down which he attributed to the DMF (For info: quoted £700 to replace DMF+clutch).

Here come the questions (thank you for your patience :Blush2:)

1. could the noise be attributed to the failing DMF?

2. although the DMF hasn't failed, but is clearly failing, should the garage replace this under warranty?

Okay, turned out to be 3 questions.

Bring on the answers!

Thank you.

TDiBoraSam
22-02-2012, 01:28 PM
I can't answer part 1 - someone else with better knowledge than me might be able to shed some light.

Part 2:

I'm not aware that a failing DMF would cause the noise you're describing. Nor would it necessarily be the cause of engine shudder on shutdown - that could be something else such as a dodgy mount? It depends what is meant by 'shudder'.

A couple of ways to tell if the DMF is failing are: When the car is idling, there would usually be an on and off shaking felt through the car..ie: it shakes for a second or two, then goes OK, then shakes again etc etc. This would stop if you apply a few revs.

The other way is to drive the car, and leave it in a higher gear than you usually would. For example, if you have a corner or roundabout that you would usually use 2nd gear, try it in 3rd, and as you accelerate away, if there's excessive shuddering, that could indicate a failing DMF/clutch.

If it is failing, perhaps a Sachs solid clutch conversion would be cheaper and more reliable than another DMF. They are pretty needless pieces of kit on a normal road car.

Brawn
22-02-2012, 02:28 PM
A couple of ways to tell if the DMF is failing are: When the car is idling, there would usually be an on and off shaking felt through the car..ie: it shakes for a second or two, then goes OK, then shakes again etc etc. This would stop if you apply a few revs.

yup, but doesn't always go away after a quick throttle prod.


The other way is to drive the car, and leave it in a higher gear than you usually would. For example, if you have a corner or roundabout that you would usually use 2nd gear, try it in 3rd, and as you accelerate away, if there's excessive shuddering, that could indicate a failing DMF/clutch.

Will try this.


If it is failing, perhaps a Sachs solid clutch conversion would be cheaper and more reliable than another DMF. They are pretty needless pieces of kit on a normal road car.

To many conflicting opinions on this with many discouraging going SMF. Will stick to OE, I think.

Cheers Sam

phil miller
22-02-2012, 07:04 PM
It sounds very much like the front tyre is out of shape, try putting the spare on and if the noise has gone then you know what the fault is

TDiBoraSam
23-02-2012, 01:45 PM
No probs.

The shuddering does seem like DMF then.

I have also read mixed reviews about the DMF conversions, but there are sooo many reported failures of DMF.

The Sachs conversion seems to be stronger than the Valeo one. If my DMF ever failed, I'd go for the SMF, purely for cost reasons. I've had two cars previously that had failed DMF's - one VW and one Citroen. I ended up changing car, when really I should've just gone for an SMF conversion.

DMF's belong on heavy plant and machinery really.