Post 12 (attached thread) suggests a certain driving style may solve the issue of a partially blocked DPF.
short journeys, sedate driving and Not completing Full Regens of the DPF (which are far less frequent on a T5 than T6 onwards) are known to have the potential to causes the DPF to become clogged.
As
@andyinluton suggested, getting the engine hot and using the engine exhaust pressure to force hot exhaust gases through the DPF is a key factor in clearing it.
There are a pair of differential sensors (before and after the DPF) These monitor the differences between the two & will throw up a fault light if the difference between the two sensors is above a certain parameter (which indicates a blocked DPF.
Obviously you will need the van to stay out of lip mode long enough to get it to full operating Temp (oil 90+ degrees C) to give it a chance to clear The potential blockage.
The key is to keep Engine revs above 2500 rpm at all times
You may have to drive until the EML light comes on, stop, turn off for five minutes to reset the limp mode then try again whilst the engine is hot. (Keeping engine revs above 2500 at all times)
if the light turns Red do not continue to drive.
Hi our engine emissions light came on about a month ago after a longish journey. I had a guy do a forced regeneration on it which solved it. It has now came back on, it’s yellow in colour. Has anyone had this and if so can you give any advice/tips. My guy said he could remove the dpf and...
vwcaliforniaclub.com
failing that a Regen can be “forced” using software,
Carista, VCDS, etc.(search the forum)
Similarly DPF cleaner additives are available although I have no experience of any particular product.
Please do report back to assist others