Shaking at idle

**robat282** · 30-01-2008,09:39 PM

Well title says it all really, my Bora has, in the last week, decided to start shaking when it's cold and idling, when i dip the clutch it seems to stop, it also seems to be fine once the car has warmed up. Am I right in thinking this is to do with the flywheel?

Also, I seem to have cracked the plastic under the engine which the sump guard attaches to. Not at the front but on the offside and at the back of it, looks a bit like a tear?! I'll try and upload a photo at some point. I don't recall racing over any speed bumps, so not sure how I've done this!

**vwbora-driver** · 31-01-2008,01:29 AM

I have the same shaking in my car as you have mentioned and i have been told it is either the flywheel or the release bearing in the clutch but mine has been doin it for about a year now with no other problems so i am not fixing it until it is broke!! as for the piece of plastic under the car it is very easy break if it is trailing i would just remove it as it only makes it harder to change the oil.

**robat282** · 31-01-2008,11:43 AM

ok well i'll leave it for now then!

as for the plastic, it's not the piece that bolts onto the underside of the car, its the piece that has the screw holes for that piece of plastic, like i said i'll upload a picture cos it's difficult to describe, not sure if you can easily remove it...

**TDiBoraSam** · 31-01-2008,01:22 PM

It's definately a clutch and flywheel problem. My car had exactly the same problem, only at idle, when cold, and stopped if clutch pedal was pressed. If you do get it fixed, make sure the clutch is replaced too, and not just the flywheel, or else the problem will just come back again....as mine did.

I'm not sure what long term damage is caused by continuing to run the car with a broken flywheel? I assume eventually the clutch will just break?

**vwbora-driver** · 31-01-2008,01:57 PM

I think my clutch will break eventually but i am not goin and spending a couple of hundred pounds to change it when it still works fine and hasnt got any worse. I think i know the piece of plastic you mean i think it is only held with two clips it should just pull off.

**robat282** · 01-02-2008,06:31 PM

spoke to my mechanic this morning and he was saying that for some vehicles there are conversion kits, so you have a normal fly wheel and the springs or what have you are fitted to the clutch, anyone heard this?

**butch** · 04-02-2008,01:14 AM

yup, i fitted one 2k ago.....99 110tdi, a valeo one, some people think that you should stay original flywheel, ie Dual Mass, i was looking for a cheap way out and it works fine for me, incidentally, mine is re-mapped too
Hope this helps
The Valeo part no for the 4 piece kit was 826517 for mine i think but i can check that tomorrow
Regards
Butch

**Pauloz** · 04-02-2008,05:35 PM

Originally Posted by robat282

spoke to my mechanic this morning and he was saying that for some vehicles there are conversion kits, so you have a normal fly wheel and the springs or what have you are fitted to the clutch, anyone heard this?

Be careful. The DMF is there for a reason, to prevent damage to driveline components, even if youre not worried about a slight increase in cabin vibrations. Vehicle manufacturers wouldnt increase costs by fitting it unless they thought it worthwhile. This solid flywheel replacement, covers around 6 different LuK and Sachs flywheel references...... how can that be designed specifically to reduce the torsional vibrations for your vehicle? There is no way a driven plate, moving around 18 degrees maximum, could absorb the same vibration as a DMF that rotates 100 degrees...... IMHO

A DMF should easily last 100k, and i have seen double that.

**vwpd130** · 07-02-2008,01:48 AM

the TRUE cure for this problem is a new ECU

hard to believe i know, but the same happened to mine (almost ran o 3 cylinders after about 2 miles from cold) and luckily i had a used car warranty, and also i am working at a VW dealer so i searched the TPL files and found tht this was a fault with the warm up phase and is a known issue

a new ecu cured the fault 100%

they dont mention WHY pressing the clutch cures it, however, theyt do mention that pressing the clutch will stop the idle judder

**Pauloz** · 07-02-2008,08:57 AM

Originally Posted by vwpd130

the TRUE cure for this problem is a new ECU

hard to believe i know, but the same happened to mine (almost ran o 3 cylinders after about 2 miles from cold) and luckily i had a used car warranty, and also i am working at a VW dealer so i searched the TPL files and found tht this was a fault with the warm up phase and is a known issue

a new ecu cured the fault 100%

they dont mention WHY pressing the clutch cures it, however, theyt do mention that pressing the clutch will stop the idle judder

Very interesting - do you have a link/downloaded file availble with this info bud?

The only reason i can think of, is that the engine not running correctly causes more vibrations out of the crank, which subjects the DMF to more torque than its designed for, and is probably still what causes the knocking. Pressing the clutch may stop the flywheel bouncing around so freely/noisily as the extra pressure from the release bearing could stop it rocking laterally..... possiby!

If this is the case, and its only my logic, not fact..... I can't see the DMF not being damaged. If its knocking, its wearing.