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New vw jetta clean diesel not so clean

My aunt bought a new volkswagon clean diesel sadan and the problem is that if they saw it’s a clean diesel why does it leave black spots that I think is soot all over the bumper mostly around the muffler area? This looks really bad because her car is white


  1. How long ago did she buy it? What is the model year?
  2. Is she buying the right fuel for it?
  3. Is the required fuel low Sulfur diesel (LSD) or ultra low Sulfur diesel (ULSD)?
  4. Might she be filling it with farm diesel fuel to save money?
  5. What does the dealership say?
  6. Is it still under warranty?

A month ago so it’s a 09 Yes she buying it at shell and chevron an she use to have a older jetta diesel so she’s use to going I diesel gas stations, I don’t know what farm diesel is so she doesn’t use it, they said it’s normal but who would want a car that the whole body is clean except the bumper and the spot looks like you lit it on fire? It has the basic warranty, what might it be???!?!?

You must keep pursuing this with Volkswagen. We have had reports of poor customer service at VW Dealerships.

Yes and when I see vw jetta tdi’s on the road they have the same problem too but only the ones that are dirty

As noted, she needs to follow up with the dealer on this one. Make sure she keeps documentation on it as it may end up as a Lemon law event.

They should be able to fix this one. There are only a few things that are likely the problem and the should be corrected.

While I like their cars, I am not very impressed with their dealers. As it happens I hit a good one and they have done just fine for me. But I know from all the complaints I hear from others that it is certainly not universal.

The symptoms sound similar to what happens to a commercial truck with a blown turbo, but it could be many other things as well. I also wonder if she is using LSD in a vehicle that might require ULSD.

First, you need to confirm it is getting the right kind of fuel. Then, you need to take it to the dealership while it is dirty to show them and get it fixed under warranty.

That isn’t the kind of clean that they mean. A diesel car will always be smudged and ugly in back.

Funny you should mention this, because just the other day I noticed a brand new white Jetta TDI, and it too had soot all over its back bumper. I guess these cars still put out a lot of particulates. Maybe VW should sale this car only in colors that don’t show soot on the bumper.

A diesel car will always be smudged and ugly in back.

Many do but many don’t. Mine does not. It has less soot on the back than many of the gasoline cars I have had.

How it is driven, and how it is adjusted can make a really big difference.

A timing difference (injection is timed not the spark) can cause smoke and hard acceleration can cause the smoke. If I really want to, I can make a rather impressive black cloud, but in my normal everyday driving, No one would know I drive a diesel.

But this car is new how can I have problems already?

His point is this might not be a problem. It might be a matter of driving style.

You need to take this vehicle in to get it checked out under warranty. There might be something wrong, but there might not. If there is nothing wrong, you might have to pay for an hour of labor for the diagnostic work.

But this car is new how can I have problems already?

I don’t know there is a problem. If there is then it should be taken care of by the dealer. However it is possible that there really is no problem, in which case the dealer is not at fault.