Hi guys,
I’m at wits end trying to understand why and how exhaust comes into to the vent and cabin. It’s only on colder days and happens after 3-4miles or after 10min drive. Seems to be connected to engine prewarmer or burner or something. I can see exhaust appearing through the windshield on the driver side, the burner exhaust goes as it should under the car.

I cannot see the source of the leak, when I pop the hood, the exhaust disappears and no specific smell is present at the engine, but it smells real bad where the air intake is at the windshield. After a while driving with the windows down, the exhaust disappears and doesn’t come back. What can it be? Leakage from the burner? Crank house vent? Manifold?

Doesn’t seem to be “engine” related, what components are on the driver side, beside the burner?

Much appreciated for any suggestions, it’s a 2015 TDI, 262hp, v6.

 

Have you checked the flexible sections on the exhaust?
There is the downpipe, and also a section on the exhaust manifolds

 

Hmm, clamped together or welded section? Will check.

 

Turbo, EGR, downpipe etc can all do this. Look for soot deposits as a telltale sign

 

Ok, so it is obviously not the flex. The shop fixed it. Today I managed to capture a very obvious leak. I will try to post the video, there is a lot of exhaust coming up through the driver side wheel house up to the cabin intake. It’s very clear that there is something going on there, and doesn’t look like the heater. What exhaust things are directly under the intake under that side?

 

 

The video would be good. The downpipe is on that side of the engine.

 

Absolutly fuming, I will try uploading the vid. Difficult with white smoke on pictures though…

 

Hmm… see how i can post it, but it is fuming from this place…

 

Video of exhaust

the strange thing is that there are no obvious leaks visible (turbo, flex, injector, engine, etc.) from engine room and nothing under… must be somewhere not easily accessible..

 

Says "video not ready yet" ??

 

Maybe you have an injector seal leak. This would run out of the weep holes built in the valve covers and down to the exhaust, creating smoke and burnt diesel stink. Depending on how bad the injector leak is, it will be a lot of smoke or very little, but you'll smell it for sure.
By removing the pop off engine cover, you can see if you have a dirty looking black stain running down from the valve cover onto your exhaust. It will look a lot like the baked on oil found in a grill or inside an oven.

 

Thanks, will check, the mechanic did repair a faulty injector this spring… 🤷‍♂️ however even if I pop off the engine cover, there’s nothing visible like what I can see close to the cabin air intake, that’s what’s confusing me. The exhaust magically appears only there and not anywhere close to the engine, could be a leak that drips to some warmer parts, but there’s nothing on the ground, like an oil/gas leak for example.. Will do more research this evening and post.

 

Try this one:
Video exhausts

so, it is clearly not: injectors, turbo, flex pipe, the manifolds, downpipe (at least not what is visible from beneath the vehicle). I cannot see where it originates, I am starting to lean to that there is something going on with the diesel burner/pre-heater or “above it”, however the heater has a different exhaust pipe (which works), unless there is a crack above somehow/where.

I am going back to the shop tomorrow and have them search, but it’s frustrating, it is a lot of smoke, but I cannot find the source, it remains hidden sort of.

 

That one works. WTF tho! What is even over there?! I can't fathom what's smoking right there! What does it smell like; fuel or exhaust

 

Awesome video!! Not an injector seal. If it was me, I would drive it up ramps, pull the plastic engine dust shield down from under the engine and get on a creeper to take a look at the exhaust system from the DPF filter back to the engine bay. Trace the exhaust, that's a lot of smoke, and there has to be a leak. It has to be an exhaust leak near the left side I would assume. In the US it would be drivers side.

 

Yeah, I am leaning towards doing that more than vs. having the repair guys doing it. I’ll keep you posted. It has to be something above the auxiliary heater close to the wheel house.

with that much smoke, you would think it would be easy to find the source…

 

SO! I returned to the shop and they will do some more investigation into the matter. However I am fairly certain that it’s the pre-heater/parking-heater/“webasto” that is the culprit. I don’t know if there’s a flex pipe that may break/rust there as well.

The heater is located under the driver’s seat, which was what I suspected from the beginning, but the shop found other issues and repaired those, but not this.. 🤷‍♂️

 

Ohhhh I don't have any experience with those but if what you are saying is accurate, then I 100% believe that is related to the heater

 

Ok, so the issue is and was the exhaust from the webasto. There is a flexpipe there connected to the rest of the piping going to the outlet under the vehicle. Thanks for the help, on the postive side, I have learned quite a bit about combustion engines in modern cars by now. 😀

 

Good find!

 

Hi all,
Just wanted to update on the issue. It wasn’t the exhaust, the whole aux heater was end of life. Completely new was needed, it wasn’t webasto, but ebersprächer. The burner is located by removing the wheel in the driver’s side and removing the wheelhouse protection. Unfortunately as the vehicle had 16,000 European miles on the gauge, I had to pay the full repair myself, 3000usd. 👎

Now the vehicle unfortunately again (after one week) throws a lot of gang signs, auto hold error, park assistance error, chassi error, start/stop error. I am suspecting this to be battery related, since these burners use quite a lot of battery, and it’s 9years old, but it’s back to the repairs next week… again… the car starts however…