Hi All,

I have an 05 1.9tdi (130bhp) superb, my second one. When the car sits idle cold or hot the engine is shaking and vibrating alot. Have had all the usuals checked engine/ gearbox mounts all fine. Also shows no faults on VAG computer.

Car runs perfect otherwise but is bugging me as I no the previous one the engine looked solid when idle. If you increase the revs very slightly on the accerater it is fine.

Any ides welcome folks?

Sounds like you could have a dual mass flywheel problem there my friend have come across lots of them giving the same symptom you have !! looks like gearbox removal is on the cards.

Lemme know when you find out cos mine is feeling a bit loose, I suspect the engine mounts, although they may look ok, if they are soft they will cause these symptoms.

I agree its a DMF issue.

DMF - so what is this all about?

Mine may be having the same problem - but I have just got it back from the accident repair place and now seems shakey at idle and previously sterring at idle was childs play - now it is a pig, with intermittent power steering assistance . In fact it is just like having a loose or over tightened power steering belt.

Can you tell us more about the DMF please - ie what is it, what would need replacing, oh! - I assume that, as it has three letters, it will cost - right?

Thanking you kindly in advance.

Perhaps before you go the 'expensive' route get a double check on the idling speed (because, as you state - if you increase the tickover speed a touch the problem goes away).

DMF - so what is this all about?

Mine may be having the same problem - but I have just got it back from the accident repair place and now seems shakey at idle and previously steering at idle was childs play - now it is a pig, with intermittent power steering assistance .

Thanking you kindly in advance.

If you are having problems with the steering assistance, check the one way clutch in the alternator pulley. These fail at about the mileage of your car (or usually a bit less) and cause the drive belt system to oscillate at idle - have a careful look with the engine running. A new pulley is cheap enough but you officially need a splined tool to hold the rotor whilst you remove the pulley nut. There are other ways...

Find a good independent with the right tool.

rotodiesel.

...you officially need a splined tool to hold the rotor whilst you remove the pulley nut...

You always manage to make me laugh when I'm at work Roto. Good times

I said "officially" because I was once stuck with a faulty pulley on a Passat. I also used to work for a Company which made alternators (bigger ones)...

If you have to do this job unplanned, take the alternator off and dismantle it so you can get at the outside of the rotor claws. You can then hold the rotor very firmly in a workmate and unscrew the pulley nut without the splined key. Don't attempt this unless you know what you are doing with alternators though.

rotodiesel.

Oh dear, this sounds as if it is getting to be a bit pricey.

I look after my cars and do not drive them hard - one wonders if I am born unlucky when it comes to buying second hand cars.

I think it may be time to obtain a Haynes manual - or at least start a search.

Many Thanks for all those who have contributed.

I have booked the car in for Friday afternoon (not the nest time to turn up at a garage) for the accident repair centre to look at it to see if it is something they have done or have been involved with.

I will keep you all informed.

P.S. - I now have my parents car to drive - a Volvo - now there's a thought...

I think it may be time to obtain a Haynes manual - or at least start a search.

Good luck on that...

As Roto has correctly pointed out recently, the Superb is really just a "Passat in drag" so I'd buy the Passat manual that covers the correct years.

I believe this is the one, book #4279:

This will cover the majority of things you'll need to know, although I suspect if you're unlucky enough to own the 2.8 V6 petrol you'll be out of luck.

(I don't think the Passat came with this engine did it? Wasn't the big engined Passat a W12? :confused:)

Passat did have a 2.8 in four motion guise.

A quick check on the Haynes website confirmed that there is no Haynes for the Superb.

However, you have answered my next question - I will acquire said book and check it out - I remember my student Land Rover days and working on them (the Land Rovers that is!) all times of day and night and in all weathers...

Thanking you all again for your help.

I will keep you posted.

A new pulley is cheap enough but you officially need a splined tool to hold the rotor whilst you remove the pulley nut. There are other ways...

Find a good independent with the right tool.

rotodiesel.

Would the age-old method of holding the pulley with a belt wrapped around in a vice work?

Passat did have a 2.8 in four motion guise.

Thanks Lummox.

Did I imagine the W12 then? If not, I'm assuming that was 4x4 as well. An FWD W12 would be, er, interesting...

Would the age-old method of holding the pulley with a belt wrapped around in a vice work?

It's a pulley with a one-way drive in it which stops you doing this. Solid pulleys don't fail.

rotodiesel.

Well, I have found out what I the problem is.

I understand that there is a pulley tensioner at the front, of the engine and that pulley tensioner is a self-tensioner (so I understand but please correct me if I am wrong). It appears that this has failed as their is little tension in the belt. This would explain the juddery power sterring at idle and the appearance from time to time, of the alternator light.

So, assumed that I have fathomed that out, now I need to remove it, replace it and fit a new one (assuming there is no trick to correct it). That could be an evening job or Saturday (I guess?) but probably my friend at DBS will get this one done.

I don't think it is a radiator out and bumper off jobjob, most likely a fan out job - just depends how long the spline on the bot holding the radiator is.

What are all your thoughts on this pulley tensioner?

Alternator - I remember when I repalced my Land Rover stupidly low amperage one with one from an MG Montego with double the amperage - it was great the interchange of parts on Rover, Austin Rover and all associated companies -a bit like VAG group.

...I have not yet worked out which part of my car is the bit that relates to Bentley...

Easy why to check lley has failed.

Take a long thin electrical screwdriver. With the engine OFF poke the screwdriver into the alternator (carefully) and try and turn the internal fan blades. If it turns one way but not the other its fine. If the blades wont turn freely then its knackered.

To change the pulley you need to pop the alternator off, the front doesn't need to come off for this.

It's a pulley with a one-way drive in it which stops you doing this. Solid pulleys don't fail.

rotodiesel.

Aaah. I was trying to visualise where the one-way clutch was- From your answer I presume it's part of the pulley itself. Thanks.

Yep it is.

From what I remember the one way pulley was originally invented as the high compression on a diesel rotates the engine half a turn (or so) backwards when you turn it off the tension on the aux belt was sufficient to undo the pulley.

Had loads on the Sharans etc that fell off.

ah, I think we are talking about slightly different pulleys.

My pulley that has failed is the tensioner pulley - can anyone help with that?

Its part of the tensioner