Why's My 2.0 TDI Running Rough on Idle? (With Vid)

Update - when i put the AC, it idles ok :S

Put as soon as it goes off, she idles rough again...

Any help would be really apreciated!
 
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wow sounds ruff that mate hope you get it sorted see you fit your turbo then do you think any bits off the turbo went in the engine or something probably a silly comment i know but not to clued up on engines .....
 
it been working fine with the new turbo and it was all flushed out so defo nothing to do with the turbo.

Someone said maybe re-gassing the ac may help :S
 
sorry mate i meant the old turbo you know when it blew up ...probably nothing to do with it hope you get it sorted though mate
 
It was flushed out so the remains of the old turbo would have gone out but it only does it at idle so that reeassures me that th engines ok.

It use to do something similar when there was an air leak.

Is there anyway i can adjust the idle level via vagcom? I heard someone speak of it before but cant remember who :S
 
Dual mass flywheel chatter, causing load to come on and off, thus causing irratic idle would be my first guess

How many miles has she done?


Edit scrap that as just noticed it said DSG:redface:
 
Mine does axactly the same, but not all the time. When you put the AC on it goes away. Had mine on VAGcom, no codes.

Midnland VW told me it could be a clogged EGR valve?
 
Dual mass flywheel chatter, causing load to come on and off, thus causing irratic idle would be my first guess

How many miles has she done?


Edit scrap that as just noticed it said DSG:redface:

60k with 95% motorway miles :D Im sure the dsg is fitted with a DMF but im pretty sure mine is ok :D

Mine does axactly the same, but not all the time. When you put the AC on it goes away. Had mine on VAGcom, no codes.

Midnland VW told me it could be a clogged EGR valve?

I think I'm onto a solution - just need to do a bit more research and try it and will let you know how i get on tommorrow!

Fingerscross
 
Mine does the same, not all the time though.
 
Off-topic:
I thought automatics don't have a DMF???
DSG is not an automatic gearbox, it is a robotized manual. It has almost the same configuration as the manual gearbox only that has 3 electrical motors that engage/disengage the clutch, move the gear selector left-right and one tha moves the selector up-down. The power is transmited from the engine to the gearbox trough a clutch not trough a torque converter. So it does have a flywheel and is the stupid dual-mass one. I've already changed mine at ~55k miles.

On-topic:
Check the EGR valve. It has the bad habit to clog.
 
i dont know if diesels have a MAF sensor but when my S3 idled funny like that it was down to the MAF, If it has one unplug it and see if car idles fine then, Hope this helps
 
Hi guys - thanks for the suggestions.

EGRs fine (as that was the firt thing i cleaned) as are the injectors but i have found out 2 ways of how to sort it (but i am yet to do so).

1) adjust the idle speed level via vagcom like this:

"select engine ,go to security access login using 12233 then go to adaption think its block 3(could be higer /lower) adjust then test if its ok save" (Hollow from uk-mkivs)

He also told me that 820 was found by Audi to resolve the rough idle issue. Car has to be warmed up when you do it though. But if that doesnt work:

2) adjust the torsion value on the timing, it doesnt look too hard: http://forums.tdiclub.com/showthread.php?t=215202&highlight=idle+speed

I'll be giving it a shot soon - Hope this helped out you guys in a similar position as it took me hours of research and posting on many forums to find out!

Will lt you know how it goes but I'm quite confident!

Cheers
 
no as the cambelt stretches a little or different tolerances in cam belt manufaturers ,mechanics fitting them etc the timing is to retarded advancing it a few degrees gets rid of the rough idle with no negative impact on the running or starting of the car .

the dmf is another issue and adjusting the timing or idle speed wont hide the fact that the flywheel is knackered
 
no as the cambelt stretches a little or different tolerances in cam belt manufaturers ,mechanics fitting them etc the timing is to retarded advancing it a few degrees gets rid of the rough idle with no negative impact on the running or starting of the car .

the dmf is another issue and adjusting the timing or idle speed wont hide the fact that the flywheel is knackered

That might explain mine, its due a cambelt in 8k
 
Cam timimg was out.

The torsion was at -3.9 and so it had it adjsuted to between -2 and 2.

To do it, loosen the 3 bolts on the first cam and then nudge the middle bolt clockwise to advance and anti clock to ****** it.

I still need to do it but pretty sure that will sort it! I jsut had my cambelt done a few miles ago and then the juddering strated so it must be that.

Will give it a shot when i get time...
 
Can I ask if you got round to adjusting your timing and if it cured your problem ? Also I think I might have the same problem, do I need the vagcom software to be able to check my timing values ? Could this also be the cause of my warm start problem ?

thanks
 
My brothers car 2.0 tdi was doing the exact same thing.........changed the coolant sensor (2 pin) and all is ok now. Best go down that route first, 1..its a cheap fix and 2.. it controls the air/fuel mixture settings.
 
Yes -adjusted the timimg torsion and it sorted the prob ad yes you need vagcom to check the torsion value.

Coolant sensor was changed on mine but it didnt help but vagcom said the timing was out so it sorted it :)
 
I had the same problem. They dont really know what is causing the shuddering on idle. But they did say that it may be one of the fuel pumps that need replacing. Aparrently the fuel injection in my car at idle is very low and that is why the engine is shuddering as it struggle with not enough fuel.

Any opinions?
 
Where on Vag Com can you check the timing?
 
Mine eases when i have the AC on, but i don't have the resources to check the timing stuff, ill just live with it for now..
 
well my dmf was knackerd and has been changed .
timing is set to 0.5
if ac goes on it stops
i can turn tick over up it stops

gear box outputshaft has alot of play in it so could this cause it..recon one on order
or should i advance my timing ?
 
What should the torsion value be ? mine is -2.0 and is idling perfect where as the other a3 i looked at which was idling rough was -2.4
 
between -2 and +2 and that should be ok !

There's a little bearing in the engine (flywheel bearing i think) - might be worth changing that wih the gearbox shaft..
 
eurocarparts best price i got was 440 for dmf and clutch and slave.. including vat and thats a very good price
 
hi there is it a BKD engine? they are prone to injector wiring looms going down intermitantly also i'm pretty sure there is an engine ECU update to sort the erratic idle out
 
according to audi there is no ecu update for my bkd engine..
no fault codes .
just a judder when cold till warm...

fixed my hot start fault with a new starter motor....

so would the wiring loom show up a fault ?
 
Just wondering what is the consensus on reliability of the 2.0L TDI engine etc?
I have had my 2004 2.0 Tdi Sport for 12 months now and so far i have had to replace the turbo, replace the EGR valve, replace an injector loom and now the ****** flywheel has gone!! It also idles like a tractor to the point of nearly making you feel sick at traffic lights, I have had it serviced to the book twice ove the 12 months!

The dealer let slip that these new engines in Audi A3/A4's and Volkswagen Passats/Golfs are absolute nightmares and really poor in terms of reliability.

Am i alone in these problems?
 
Just wondering what is the consensus on reliability of the 2.0L TDI engine etc?
I have had my 2004 2.0 Tdi Sport for 12 months now and so far i have had to replace the turbo, replace the EGR valve, replace an injector loom and now the ****** flywheel has gone!! It also idles like a tractor to the point of nearly making you feel sick at traffic lights, I have had it serviced to the book twice ove the 12 months!

The dealer let slip that these new engines in Audi A3/A4's and Volkswagen Passats/Golfs are absolute nightmares and really poor in terms of reliability.

Am i alone in these problems?

Ive had the same probs mate but not theflywheel one.

Not very reliable to be honest...but then theres some which have done 120k without a single glitch :s
 
Am i alone in these problems?

The previous owner of my car had to change the flywheel. I've read on another forum about the injectors, they are very unreliable. Someone changed all several times but they keep breaking. Also there is a problem with leaking coolant.