2009 Jetta TDI suddenly has a miss

Hello all,

Long time lurker but first post. This is my 1st VW and I have been really enjoying it. I'm a fairly good mechanic but am not versed in the ways of the VeeDub.

My 2009 Jetta was running fine when I parked it and the next morning has developed a miss. At first it seemed to only miss when idleing but now it's doing it all the time. Ive only driven it about 5 miles like this. No CEL light. No idle speed fluctuations. Just a very obvious miss with a vibration. The car has 133,000 miles on it and had the timing belt and fuel filter changed (at the dealer) right after I bought it at about 110,000. I haven't been overwhelmed by the fuel mileage (high 30's) but my understanding is the CR's don't do as well on fuel.

I have VCDS but am not sure what to look for to confirm if it's a dead/clogged injector or a wiring problem. Will VCDS do a "buzz" test or cylinder contribution?

EGR and DPF were removed right after purchase as well as Malone stage 2 and DSG tune.

Thanks for any help/direction anyone can offer.

Does the engine run OK? No smoke or anything? Could it be your are thinking a bad vibration is a miss when it isn't? DMFs coming apart will feel much like a dead cylinder.

Try checking group 13 in the engine controller with VCDS while experiencing the vibration.
If any of the readings are nearing nearing +- 1.5-2.0mg/str or greater variance then you could have a cylinder issue. Otherwise, I would also suspect a flywheel issue.

Oilhammer - no smoke or other problems just a vibration at idle thaf will tickle your ears. I suppose it could be a flywheel.

JETaah - I will try that and post back with results.

The car is a DSG trans, that will still have a DMF, correct? If it's a flywheel, is there a better one than factory? That won't be a job I want to do twice.

Yes, the DSGs have a DMF.

I have a new in the box Luk brand (the OEM supplier) I will sell for pretty cheap if you are interested.

I bought it for a car I was going to purchase but ended up not buying the car, been sitting here gathering dust ever since.

Oilhammer - I'll shoot you a PM

Well, I hooked up the VCDS today. I checked the group 13 as JETaah suggested and the highest variance was -.21mg/str with a high of .12mg/str. So I guess that rules out a miss or stuck injector.

Unfortunately I also found a 17252 code for low DSG oil pressure. The car has been religiously serviced by the dealer since day 1 and the DSG was serviced about 30k miles ago at the dealer. It shows the code was set approx 3k miles ago!! WTH? Seems that should have thrown a CEL. I reset the code and it came back. I don't see any signs of leakage and the trans has been shifting fine from what I can tell. So, now I'm thinking catastrophic damage to the trans is causing the vibration....??

The vibration isn't as bad at start up but gets progressively worse as it warms up. It's a LOT more severe at idle and smoothes out some once up off idle.

Ugh...I'm just sick.

Update - car is FIXED!!! I'm pleased to report the car is smoother than ever after replacing the DMF. I want to extend a big, public "THANK YOU" to oilhammer for answering the endless questions through PM and helping me fing a good deal on a replacement flywheel. Great guy and a great forum. Thanks again!!!

Awesome, glad you got it fixed!

How can you know for sure that you have a failing DMF. My car is not at the point where I can feel any vibrations inside the car or hear any abnormal sounds inside.

I do see the engine move a bit on idle and I hear a rattling noise from the DMF area. Some say the noise still presists even after a replacement or returns shorlty after.

Is a small amount or any amount of engine movement normal for these engines?

Or can I be certain with those 2 symptoms that I need to replace the DMF ASAP

A little bit of noise is OK, and normal (even though a "new" one won't do that, if you replace the DSG's DMF every time that noise starts, you'll be replacing it every 40k miles).

The vibration can get pretty bad, it will be pretty obvious. The car will shake like it is running on 3 cylinders.

So its safe to wait until there are actual noticable vibrations.

I assume if neglected when the symptoms are very pronounced it could cause damage to the transmission as well?

My car is at 211K Miles (340K Kms). I'm sure its still the original DMF.

We're planning on taking a 6000 mile road trip this summer across the country to California. Would not want to get stranded because of something like this.

You will (should) have plenty of warning that something is not right.

But in extreme cases, continuing to drive with a bad DMF can cause:

DMF to blow apart and send chunks through the bellhousing

Beat the splines up on the input (clutch) shaft as well as the splines on the DMF itself (car stops moving)

Beat the pilot bearing to death and tear up the crankshaft (had to R&R a crank and have machine shop drill it out oversize and make a sleeve to press down in there.... otherwise replace the $1100+ crankshaft)

Keep in mind, ANY engine that has a DMF (and there are lots of them), can have these issues. Nissan, BMW, Ford, Chrysler.... seen 'em all fail.

Here's a video of the noise.

Its not constant. It starts at about 14 seconds and last for a couple seconds before it goes away. Its on and off while I'm at idle.

https://photos.app.goo.gl/tJzgj9AA3lt27UTE2