Shakes ever few seconds on tick over

[rich68a]

I have a 2005 Audi A4 2.0 TDI Avant. 54k miles with FASH.
I have noticed that whilst on tick over it does a small shake/wobble every few seconds. It drives fine and have had no other problems with it bar every time I put the brakes on there is a small knock that comes from the F/O/S front wheel. All brake pads are new? Brakes are not as good as our A3 which is suprising.
Has anyone got any ideas what these problems could be?
Thanks alot

Edited by rich68a on Monday 4th April 17:22

[drybeer]

Suspect idle judder is a faulty fuel injector, knock from front likely upper arm or bushes worn...

The injector any dealer with VAGcom should be able to confirm and the knock any reputable garage should be able to investigate.

[rich68a]

I had it placed on the diagnostic computer and no faults came up. It has aslo been mentioned to me that it could be the dual fly wheel. That would mean changing the clutch as well and me being £800 out of pocket.
I would tend to lean towards your thought of the injectors but besides the light wobble every few seconds on idle it runs great

[00161wj]

Has it had a cambelt replacement? If so id bet the fueling is set to low (adjusted on a cambelt change). Are they genuine brake pads? You do sometimes get a slight movement in brake pads if theyre cheap which causes a knocking.

[BoraBora]

Is it a BLB engine code ?

read up on the chain driven blanace shaft/oil pump

[anonymous-user]

I had this exact problem with my 2004 A3 2.0 TDi... no funny noises or anything, just a 'shudder' through the steering wheel every 4-5 seconds when parked with engine idling.

It was cured by the ECU being reflashed with the latest map for my engine.

Maybe try that?

[rich68a]

Thanks for your replies. Keep your ideas coming as I dont want to spend £800 for a new dual fly wheel and clutch when it may not even resolve the problem.

[jj333]

Cambelt & waterpump helped on mine, but I also find millers additive reduces it a lot too

[Tame Technician]

rich68a said:

I have a 2005 Audi A4 2.0 TDI Avant. 54k miles with FASH.
I have noticed that whilst on tick over it does a small shake/wobble every few seconds. It drives fine and have had no other problems with it bar every time I put the brakes on there is a small knock that comes from the F/O/S front wheel. All brake pads are new? Brakes are not as good as our A3 which is suprising.
Has anyone got any ideas what these problems could be?
Thanks alot

Edited by rich68a on Monday 4th April 17:22

That slightly rough idle is normal for the PD 2.0TDI.

You can sometimes improve it with an injector clean and injector oring seal relacement. But if there is nothing else wrong with it I personally wouldnt bother, you could chase it for ever spend loads and never fix it. They often did that from new.

99% sure That knock is the new non-genuine pads knocking in the caliper, they do that.

[subsea99]

yep mine was same, put some injector cleaner in and the difference is amazing mines is an 07 with 91k

[rich68a]

The pads I presume are none genuine and were fitted just before I had the car so will be replacing those ASAP as the knock drives me mad!
I have already had the cam belt and water pump replaced and it had that wobble before that was even done. What injector cleaner would you rcommend as that may solve the problem although wouldnt a problem show up on the diagnostics?

[subsea99]

millers or redex (what i used ) does'nt help with supermarkets mixing upto 7% biodiesel with standard stuff.

really did make a difference as it shook like mad on idle,they say a half bottle every 6 tanks or so

[Tame Technician]

rich68a said:

The pads I presume are none genuine and were fitted just before I had the car so will be replacing those ASAP as the knock drives me mad!
I have already had the cam belt and water pump replaced and it had that wobble before that was even done. What injector cleaner would you rcommend as that may solve the problem although wouldnt a problem show up on the diagnostics?

The injector clean we do is to remove the injectors and put the nozzles in an ultrasonic cleaner for 90 mins. The chemical tank addatives may well work, but are not as effective as the propper clean.

You could also drain some fuel from the fuel filter, if it is black it has been discoloured with engine oil, a sign the injector seals are leaking.

Most people who have the injector seals replaced and the injectors cleaned while they are removed to replace the seals, notice a big improvement in idle quality.

But as I said before, they do all do that a bit, and I was at the dealer when we PDI'd brand new cars, that came from the factory like that. So you will never completely get rid of it.

[rich68a]

All you comments are really helpful and I am not going to bother to have a dual fly wheel replaced and clutch as I think after reading all the comments its most probably not that.