My son has a 2006 1.6 tdci Focus on 102200 miles

It has the dreaded P242F fault Ash accumulation DIS_ASFULL Km 118458

I remover the exhaust/ DPF washed it out but water was very clean no brown water only some black particles I refitted the DPF and engine ran fine for two days but now P2458 and P242F has returned 

I did the MAF trick to clear the code but it did not last long and error is back

I know tons of info has been done on this subject so is there anything i missedid or   should i bite the bullet and buy a new part

Any advice would be greatly appreciated

 

Putting water in to it isnt a good idea unless you can forcefully flush it out. The car works, so air is passing through it as will water, the question is how much its restricted and the car is saying its a lot.

It takes a good deal of force to clear it out or a sonic bath.

For the time being thrash it at 3000RPM for a 10-20 min, if you cant do that then try an active regeneration. 

Failing that you will need to clean it properly.

I had the same problem on my C-max , flushed it out but nothing came out. The car had 155k on it and I realised just how blocked with ash it was because water would take about 10 mins to come through. If I were you I wouldn't carry on driving in it and doing the MAF trick to keep resetting - I kept on doing that and ended up destroying the turbo. Got a replacement DPF for £200 in the end and new turbo and runs well now.