More Noise/Vibration running idle

[belgian]

Hello anyone who could give me some advice on what could be wrong...

I am almost hitting 200.000km with my 2003 Superb 1.9 TDI 100hp.

Up to now it's been a fantastic car - no problems whatsoever. I've had long service intervals (longlife oil system 030W) and sticked to the service schedule and recommendations of my dealer.

Recently I had my 3rd cambelt replacement by my dealer (including other maintenance that goes with it - would need to check the invoice again just to be sure what was changed).

A few days/weeks after driving with it, I noticed that the noise/vibration the engine was making when running idle (like in traffic jams - every morning when driving to work :( or just when starting it ) was a lot worse than before. Sometimes it also made a "whining noise" - especially when starting the car. In addition to that a loud rattling noise occurred when turning my steering wheel - especially at low speeds (when parking or so). The rattling noise does not only occur at full lock but worsens when you turn it faster (especially in the onset phase of turning it). When this happens the wheel does not turn as smooth as it should (feels like intermittently it's somehow obstructed).

Last week I took it back to my Skoda-dealer, who claimed to be clueless about the cause but suggested to change the cambelt again to see if that would resolve the issue. After the change - the vibration issue was not gone (still louder noise/vibration when running on idle) and also the power steering is still making the same rattle when parking . The mechanic also took it to another Skoda-dealer for advice but these could not help and -according to him- have a similar problem on two cars they have running. The "whining noise" that sometimes occurred after starting is gone but the frustrating vibration/noise is still there. Everytime the motor runs idle (below 1000rpm) the vibration is there - when rpm goes to 1100 it reduces. As you can tell- I am not a mechanic - so am feeling a bit in despair for the moment... I've seen a few true experts on the briskoda-forum...

Any of you have a suggestion what could be cause - and cure ? :confused: A huge thank you to anyone who could help....

[rotodiesel]

Obviously a guess, not having heard the noise, but knowing some of the VAG B5.5 weaknesses, I would check the one way clutch on the alternator pulley very carefully, then the serpentine belt tensioner and its bearing. The fact that the noise increases when the power steering pump puts a load on the belt drive suggests problems in this area. Did your mechanic change the serpentine belt when the cambelt was replaced?

Let us know how you get on with it.

rotodiesel.

[belgian]

Rotodiesel - thanks for your fast reply

The serpentine belt was changed indeed - as was the water pump and some other things which are always replaced by my mechanic once the cambelt is replaced.

I'll have a look on the invoice this evening.

I'll also have a look a the one way clutch of the alternator pulley and the tensioning system of the serpentine belt. That is hopefully still just within my skills - any repairs I'll have to go to my mechanic.

Thanks again and Ill keep you posted

[belgian]

Hello Rotodiesel

I would check the one way clutch on the alternator pulley very carefully, then the serpentine belt tensioner and its bearing.

I've checked my invoice: cambelt + tension rolls, water pump and serpentine belt (2 "multi belts") + tensioner + tension rolls were changed at 185.000km (570 GBP).

Just listening carefully combined with listening/looking when turning steering wheel makes me think that you are spot-on with the tensioner bearing (I did not take off the belt but one way clutch on alternator pulley seems OK as far as I can tell this way). When I hear the rattle I see the tensioner bolt vibrating quite heavily and I see the tensioner dancing a bit up and down (or is this normal ?). Could it also be a bearing of the power steering pump or would you not hear that when not turning the wheel ? I do feel some obstruction when turning the wheel but is probably because of the serpentine belt.

I guess I'm going to call/visit my mechanic tomorrow and ask what he thinks of it. He did reassure me last time that not a lot could go wrong despite the vibration I hear but I'm not so sure now. In your opinion what could be worst case scenario if the bearing gives up ? I guess the serpentine belt would come loose and it might damage a few things in the process - what could this be ?

A huge thank you for the great advice - I'll keep you posted !