pedser

I have noticed that at 590 miles and now again at 1095 the regeneration cycle has been active. Actually noticed when turning the car off and heard the fan and the burn smell.

I know that this is normal my 335D (USA) used to do the same but at much shorter intervals.

Anyone else with a USA Q5 TDI have noticed their burn schedule?

Thanks,

Pedro

Mark P

I'm not familiar with this topic but haven't noticed anything different each time I've turned off the car and I'm now at 2400 miles. Can you tell me more about it and what I should pay attention to?

pedser

Look at this https://www.audiworld.com/forums/sho....php?t=2854201 they are talking about the same issue. DPF diesel particulate fluid and how our TDI's clean out the particulate filter.

Not a big issue on the second gen v6 Tdi specially for some folks that do not do long trips, and the inability to let the engine reach normal operating temperature. (Usually more than 10 miles of driving) The system is designed to clean itself.

P

DarrenK

Just turned 1000 miles on my Dakota Grey SLine TDI and the fan came on and there was a burn smell for a little under 10 minutes. I thought it was due to high engine temperature.

skl1

Didn't realize these had regeneration, just thought the urea injection cleaned things up. Had that regen feature on a '08 F-250 tow vehicle and everytime it went into regen mode, the power would go down and fuel mileage would decrease as it used more fuel to "burn" clean the particulate filter. I was very disappointed in that truck- it was the Ford's own diesel and it was a dog and got crappy mileage for a diesel. Traded it on a F-150 Platinum which tows great and never looked back.
I'm assuming my incoming TDI S-line+ won't repeat that scenario!!

MP4.2+6.0

Urea injection deals with nitrogen oxides. Diesels are big producers of NOx, and until the AdBlue/urea advance came along, the high NOx emissions essentially locked diesels out of areas with tougher emissions standards like CA and the other (generally west coast and Northeast) states that track now to the CA stds. Meanwhile the active and passive burn off functions are what dispose of the particulates. The active function is where some extra fuel still obviously gets burned, but the passive function reduces that.

I'll post the Q5 SSP in a reply further up to stay on the more general subject of the post.

MP4.2+6.0

Here's a link again to the 2009 Audi SSP (Self Study Program--used for internal Audi tech. and other training) on the Audi 3.0 TDI. It was put out some years ago presumably tied to the Q7 TDI. Seems quite comprehensive and interesting for those who like deep dives into engine, fuel and exhaust technology and controls. Other than a bit more power relative to the other Audi (and Porsche!) installs, it should be generally applicable to Q5 TDI's; Audi usually only puts out one comprehensive SSP on a motor unless really big changes that affect a lot of internals are made.

There is a very lengthy discussion of the separate aspects of the exhaust side of TDI's--pretty far back, it starts on p. 65 and runs to the end at page 95. The first several pages though are where you can get some of the bigger picture:

• that particulates are managed by both active and passive regeneration of the filter, and
• that the AdBlue/urea system is distinct from this and deals with the diesel's traditionally high NOx emissions (which in turn tend to be found with high compression and exhaust temps).

Rather than summarize further, the SSP should be readable either at a pretty high level by skimming, or at the advanced level if you desire.

3.0 TDI SSP link (via download): http://www.1stcallhosting.com/tech/a...17&currentdb=0

bpp

Yup, I have 543 mi on my TDI and late last week around 500 mi there was a strong odor of hot plastic at the rear.

JaXeN

Link no worky.

spijun

Try this link

http://www.1stcallhosting.com/tech/a...17&currentdb=0