Fault P245900

[Cowood3223]

Thanks @mmi for all your help.

I will take it to a garage and get them to try and flush DPF but ultimately I think I will need to replace it as paperwork says it’s been done before I bought it.

It sounds like once sorted I will need it run further tests to see if I can find out what caused the blockage, hopefully short journeys rather mechanical fault

 

[Cowood3223]

So just heard back from the garage, they reported the DPF is cracked.

Recommending a new unit plus sensors £4100 and currently on back order from VW so not expected date

 

[DXX]

So just heard back from the garage, they reported the DPF is cracked.

Recommending a new unit plus sensors £4100 and currently on back order from VW so not expected date

Seems like a very high price, did they give you an itemised estimate with part numbers and labour?

 

[Cowood3223]

I will get the quote when I collect the van this afternoon, they have priced to replace all sensors as a worst case scenario so if come out ok they won’t be needed.

 

[Cowood3223]

No parts numbers but looks like total replacement with labour only being a 2-1/2 hours.

They said they removed the ad blue sensor which was heavily sooted up and camera the DPF where there was evidence of soot build up. Wouldn’t this be the round side of the DPF where soot would be present?

Tailpipe still clear of soot so can only assume
the back pressure is pushing the soot towards the engine

 

[Cowood3223]

Hi, just wanted to provide an update

Low mileage used DPF fitted after an off van clean and new pressure sensor fitted for good measure.

Cold idle DPF pressure is now 5 hpa and warm idle is 9 hpa.

Will take for a decent drive over next few days to see when the regen kicks in. I think the van needs a regen to recalibrate the DPF app.

 

[Cowood3223]

@mmi sorry to message again,

I was checking the van today and noticed the oil ash residue hadn’t been reset by the garage so I reset it back to zero and took the van out for a drive.

Drove 35 miles on mixture of roads.

What seems strange is the soot mass measured still seemed to rise quick, after the drive it was at 11.24g, where the soot calculated was at 2.28g.

The differential pressure seems to have risen to 12.8hpa at warm at idle vs 9.8hpa yesterday.

Based on DPF app, I believe it would now regen about every 3hrs and 115miles so it’s definitely an improvement. But I wondered the DPF or pressure sensor needed resetting or if the van will adapt after regen or after it’s been driven for few 100 miles.

 

[DXX]

The true oil ash residue won’t be 0.1g as it’s a secondhand DPF, it still contains the ash from previous use unless the DPF clean is deemed to have removed it?

 

[Cowood3223]

@DXX it had an off the can clean at a specialist to back flush the ash so I would have assumed it cleared the filter.

 

[Cowood3223]

Further update,

I carried out differential pressure sensor adaption and then went for a drive, at first it gave off some strange reading as the soot measured shot up but after 10 miles the soot measured started to drop. After a further 15 miles the van started to regen even though the soot measured or calculated were not near the 30g limit so this must have been triggered by the ECU as part of the reset.

Following the regen the DPF figures were much more in line with what I would expect on a normal functioning DPF.

DPF 26% full
Soot calculated 6.90g
Soot measured 0.7g
Differential pressure at warm idle 7.5hpa

If this continues in this pattern it should now show the soot calculated triggering the regen rather than the soot measured as it did before when it was blocked.