A6 DPF Issue

[944fan]

I have a 58 plate A6 2.0TDIe. The other day the MIL lamp came on. Car was fine, not in limp mode or anything. I scanned the codes and got a P2002.

I cleared the code and took the car for a longish jaunt up and down the M1. I was a bit unsure about how to do the regen. Some sites said keep in 5th gear and have revs > 2500. Others said keep revs at 2000 in top gear. I did the later.

Anyway two days later lamp is back on.

Doing a quick google seems to suggest that often its actually the sensor that is faulty. Anyway of determining this for definite without just replacing it? I only have a basic scanner, no access to VCDS.

Should I try another regen? Whats the proper way of doing one of those?

I've had the car a few years, never had an issue. I drive 70 miles per day mix of single and dual carriageway NSL and 40mp roads. I generally cruise 10 < NSL to save fuel. Not sure if that impacts it or not.

[Dr G]

You need to get the DPF properly hot, regularly.

To help it regenerate you need to drive the engine at mixed RPM to build heat (try a motorway run swapping between 4/5/6).

If the DPF is excessively clogged it will need a forced regeneration rather than a 'do it yourself'.

The sensor on the DPF can fail, yes. A proper diagnostic here may well save you money (and stress) in the long run.

[944fan]

Thanks Dr G.

Will try another re gen otherwise will book it in an Audi specialist I use.

I saw some place in Banbury offering a DPF removal for £650. Is that kosher and will it cause problems with MOT smoke test later on? Seems if the DPF is clogged beyond rescue that is a much cheaper option.

[chimp427]

The prices ive seen usually include both dpf/egr delete and a remap too which isnt bad value and eliminates 2 major problems.
Id be interested in the effects mot time too but my guess is it would be ok, its something im considering at the first sign of dpf/egr problems.

[Adrian E]

Note that DPF removal is illegal, irrespective of whether you get caught at MOT at the moment. It is very likely (read, inevitable!) that the MOT test will become tight enough to determine whether a working DPF is present or not.

[944fan]

Adrian E said:

Note that DPF removal is illegal, irrespective of whether you get caught at MOT at the moment. It is very likely (read, inevitable!) that the MOT test will become tight enough to determine whether a working DPF is present or not.

Looks like it already has:

https://www.gov.uk/government/news/new-rules-for-m...

Wont be risking that then.

[Adrian E]

944fan said:

Adrian E said:

Note that DPF removal is illegal, irrespective of whether you get caught at MOT at the moment. It is very likely (read, inevitable!) that the MOT test will become tight enough to determine whether a working DPF is present or not.

Looks like it already has:

https://www.gov.uk/government/news/new-rules-for-m...

Wont be risking that then.

That's the physical check (visual) but there's likely to be tighter controls on smoke test as well that can tell when one has been gutted.....

[Danger]

Plus the DPF is there for a reason. Diesel particles are horrible cancer causing things, if you have a diesel you have a moral responsibility to the rest of the population to have a functioning DPF

[anonymous-user]

Danger said:

Plus the DPF is there for a reason. Diesel particles are horrible cancer causing things, if you have a diesel you have a moral responsibility to the rest of the population to have a functioning DPF

Stop the Moral bleating. What about diesel buses, trains etc? What about second hand smoke? Removing a DPF is morally wrong but no less than all the decatted cars running about. Esp the petrol cat turns the nox into Co2.

OP DPF can be removed and software rewritten, i bought vagcom off gumtree for £40.

Edited by The Spruce goose on Friday 25th September 06:10

[liner33]

Also the dpf doesnt help the really harmful diesel particles in fact they are worse in that regard , as well as nox rising massively during regeneration.

Mind you with the current focus i think dpf removal might not be a great idea but the option is to replace them on a regular basis

[Adrian E]

liner33 said:

Also the dpf doesnt help the really harmful diesel particles in fact they are worse in that regard , as well as nox rising massively during regeneration.

Mind you with the current focus i think dpf removal might not be a great idea but the option is to replace them on a regular basis

Which is why you need a working SCR setup on the back of the DPF to deal with the NOx. The DPF is very effective for larger particulate matter.

[liner33]

Adrian E said:

Which is why you need a working SCR setup on the back of the DPF to deal with the NOx. The DPF is very effective for larger particulate matter.

It is , unfortunately its the nano particles that are particularly hazardous to health

[944fan]

The MIL came back on. This time I scanned again and got P2002 & P2453. Second code seems to point to potentially faulty sensor.

Going to put it into the audi specialist next week. I can't be arsed to fart around trying to diagnose it even if I did have VCDS.