DPF issues 2012 C8 2.0 HDI

[parnell]

So i finally managed to get a diagbox working on the car and I think its the pressure sensor that is causing the P1490 and P1447 codes to come up - note the differential pressure sensor is reading ZERO despite the car running at 1216 RPM at 52 kmh...
Would be very interested to hear from other members what they thought though. thankyou!!

[parnell]

Next clue... I managed to get diagbox into live measurement mode (just ordered the nexas OBD device to make this easier going forwards) and here is what turned up.

Im confused -
1) the pressure sensor seems to work fine but yet when it threw a warning pressure differential was zero
2) I filled the EOLYS tank and reset the tank in the ECU and yet the measurements today indicate minimum additive level has NOT been reached AND 1444 Ml of additive remains in the tank (out of 1460 Ml) which is just mad - I put in 3L which is what Marc (and I believe him) told me is the capacity only two years and 5 thousand kms ago.

All assistance most thankfully received.

[parnell]

Well f*** it but i tried to give it the old Italian tune-up and the service light came on with limp mode engaging...then did a forced regeneration with the diagbox.... good news is that the differential pressure dropped a lot. Bad news is that the soot % remained the same (is that just calculated?). Im now considering doing a physical DPF clean ... car only has 132 tkms on it. Whats also frustrating is that the additive level hasnt budged either despite the forced regen...

[RichardW]

You've jumped on the back of someone else's thread, do you want me to split it out?

Roll back a bit, what issue are you trying to trouble shoot on what car?

Minimum additive level means low level, i.e. reached when the additive is nearly exhausted. There is no level measurement, it is only estimated - it looks like although the tank may have taken 3 litres, the factory programmed level was only 1460 ml, and when you perform the 'refill' procedure it just records this as the volume in the tank. This has dropped to 1444 ml, so used 16ml, which is probably not that far off for 5k km. There might be an option in Diagbox configuration to change it to the amount you put in.

I would caution against doing forced regens, this can melt the DPF if there is lots of soot present.

[parnell]

You've jumped on the back of someone else's thread, do you want me to split it out?

Roll back a bit, what issue are you trying to trouble shoot on what car?

Minimum additive level means low level, i.e. reached when the additive is nearly exhausted. There is no level measurement, it is only estimated - it looks like although the tank may have taken 3 litres, the factory programmed level was only 1460 ml, and when you perform the 'refill' procedure it just records this as the volume in the tank. This has dropped to 1444 ml, so used 16ml, which is probably not that far off for 5k km. There might be an option in Diagbox configuration to change it to the amount you put in.

I would caution against doing forced regens, this can melt the DPF if there is lots of soot present.

Sorry Richard , I wasnt aware of forum etiquette here - I originally thought the issue might be the pressure sensor - split it out if you think thats more consistent with the forum rules. Apologies to all.
Yes I didnt really want to do the forced regen. There is no soot at all coming from the exhaust - nor was there during the normal operation of the Citroen C8 that Im trying to fix.
The (reasonably persistent) error codes that I get are P1447 and P1490 - I thought it was a pressure sensor failure as reading zero pressure is just nuts. Now after reading more on the board I am more inclined to take out the whole DPF - although on the C8 its a long welded together contraption (at least its just horizontal under the car) so Im not sure how to use a pressure washer on it directly after I let it steep in some DPF cleaning overnight. Thanks for any support.

[mickthemaverick]

Just a warning, don't use a pressure washer on the dpf, you may damage it, just use whatever cleaner you choose and then rinse it out with a normal hose.

[RichardW]

Now split off into it's thread - no hard and fast rules, but it wasn't that easy to pick up what you were talking about!

Ideally you need to watch the dpf readings when driving to see what the pressure is doing. It could be a blocked pipe or a duff sensor. What is the diff pressure reading at idle and 3k rpm stationary?