My 2012 2.0 TDI Sharan has done 195k miles.

The last couple of weeks I've had an engine light on because of a gunked up ASV valve.

During that time it wouldn't do a particle filter regeneration but the car drove normally.

I've since cleaned the asv, but I'm now stuck in limp mode with the particle filter light stuck on.

I've tried forcing a regeneration with VCDS but it wouldn't accept it as the soot level was too high.

I've taken the oxygen sensor out and filled the dpf with foaming dpf cleaner, left to sit for 1hr, then started the car.

When started soot mass calculated was 55.53g, measured was 4.47g.

Left idling for 15 minutes

Soot mass calculated has now climbed to 56.26g, but measured is still 4.47g

Difference pressure was around 20hPa when I first started the car, but it's now dropped down to 10.

From what I understand this should result in the estimated value going down not up?

Oil ash volume is 0.04L.

I've owned the car for 18 months and done around 10k and never had any dpf problems before now.

The fault code won't clear.

Any help appreciated

Edited 14 May14 May by softscoop

I've managed to solve this.

I spoke to a helpful DPF specialist who ran through what they would do in this situation.

1. Run a cleaner through the DPF via the O2 sensor hole.

2. Get the car up to temp

3. Reinitialse the DPF with VCDS, effectively telling the car a new dpf was fitted

4. Force a static regeneration keeping a close eye on the exhaust temperature and pressures, running with the bonnet open.

As I'd already done step 1, they said as long as there isn't sloppy black gunk coming out the exhaust which would indicate a cracked DPF, I should be safe to proceed. EGT temperatures shouldn't get much above 650° C for a prolonged period and if they do to kill the regeneration process and let the car cool.

The exhaust was clean so I followed the process.

EGT got up to 648° and didn't climb any further. Process finished and no more limp mode.