rxbruner

This has happened after about 5% of my drives. I stop the car and shut it off. The radiator (or at least I think that's what it is) keeps running for about 2-5 minutes. There is a very faint burning smell.

Is this normal?

Soobie23

Sounds like the car is going through a regen cycle. This is normal for the TDI.

KevinGary

Plus 1 on this being simply the regen.

tjf

Or it could just be the after run coolant pump he is hearing. Those new to Audi's find it perplexing. I'm not sure what "radiator running" refers to? The fans will run too, if the coolant is hot enough.

John Simcox

Perfectly normal (DPF regeneration)and usually accompanied by a burning smell. Nothing to worry about

50pascals

The amount of Regen's your car does, and the number of them that get interrupted by turning the car off, is a function of your driving patterns. I typically drive 1 hour or more every time I get in the car. I may interrupt a regen once a month. I personally try to avoid it or take steps to mitigate it.

A ton of heat is generated during the regen cycle, so when you shut the car off, the turbo / exhaust / engine is heat-soaked. So the cooling fans run at max-speed for a time to try to cool all the stuff underhood. Most importantly, the turbo.

When I arrive at my destination, if I notice the burning smell before I shut the car off, I will usually let it run unti the regen is over. This usually happens at home.

If I interrupt a regen while I am out (a rarity for me), I will restart the car and let it idle until the fans turn off. This keeps the oil and coolant flowing and cooling everything.

If you interrupt the regen's enough where the car cannot fully complete a regen cycle(many short trips) it will throw a code and require you to go to the dealer to have them do a complete regen cycle. So it is a good idea to run the car at speed once a week or so.

Again, not a huge issue for me as most of my driving is a long commute, at highway speeds on back roads. Or long trips to other cities.