I have an Audi A6 S-line 2.0TDI 177 2013 (c7) - Multitronic Gearbox

For the past year or so you can see smoke bellowing out from under the bonnet from the engine bay and you get this awful smell in the cabin (exhaust fumes, burning oil smell).

The smoke is coming from the back of the engine to the left (as you are looking at it). The engine bay on this side is covered in black soot 

This only happens when the DPF starts to regen in traffic or after doing a couple of short journeys. I have replaced part no 03L131521 JV200 (EGR Connection Pipe) as I thought it was this but the smoke keeps on coming. 
 

Coolant and Oil levels remain the same. I don’t have any lights on my dashboard either. I can tell the car is doing the DPF regen when I get the smell and see the smoke and the car starts to use a bit more fuel.

The car runs fine, isnt down on power etc etc. Exhaust flow is OK. No visible oil leaks either.

Has anyone had anything similar? 

Edited October 20, 20241 yr by audiowna

hi darragh i had the same issue on a 14 A5 and it was the pipe just under the egr valve,its shaped like a horseshoe and a pig of a pipe to change especially the 2 bolts at the back,it solved my problem tho,is this the same pipe you changed?Greg

Hi Greg, 

Have you got any photos of the pipe you changed? 

I’ve attached an image of the pipe I  changed out. 

Thanks for your reply!

12 hours ago, coupe4 said:

hi darragh i had the same issue on a 14 A5 and it was the pipe just under the egr valve,its shaped like a horseshoe and a pig of a pipe to change especially the 2 bolts at the back,it solved my problem tho,is this the same pipe you changed?Greg

 

hi darragh i dont have a pic of the pipe but thats the one i changed alright,it had a hairline crack on it and the car is fine since,they are a common fault i was told by an audi mechanic,

2 hours ago, coupe4 said:

hi darragh i dont have a pic of the pipe but thats the one i changed alright,it had a hairline crack on it and the car is fine since,they are a common fault i was told by an audi mechanic,

Thats good to know!

This pipe was replaced on Friday there, it started to smoke on Saturday evening again but since I have posted this in the forum on Sunday morning it hasn't happened again. Although inside the car I can smell fumes but very very lightly. 

Will leave it a few more days and post an update for everyone!

Thanks for taking the time to comment!

hopefully its sorted and the smell will go away once you give it a few drives

Yes it may take a few days to burn off any residual oil.

keep us posted as to how you get on

Hi folks, just an update, I still haven't located where the leak is coming from as it still does smoke after repeated short stop/start journeys in traffic etc , to combat it tho I have just been driving the car in dynamic mode to keep the DPF from blocking and take it for a good run out every now and then and its doing the job for me at present!

12 hours ago, audiowna said:

Hi folks, just an update, I still haven't located where the leak is coming from as it still does smoke after repeated short stop/start journeys in traffic etc , to combat it tho I have just been driving the car in dynamic mode to keep the DPF from blocking and take it for a good run out every now and then and its doing the job for me at present!

Sorry you're still having issues, but at least you have a temporary cure. 

Be worth checking the turbo oil feed pipe isn’t leaking where it fixes to the top of the turbo core. This pipe will have a fair bit of pressure in it when engine is running so worth checking with engine on and off, oil loss can be very small as it is often a weep rather then it pouring out