Depollution system faulty

[Badtoad66]

I have a Citroen C4 VTR+ 1.6hdi with the error "Depollution system faulty" and the engine management light constantly on. The car is a 2005 with the VIN number 9HY which I am lead to believe is a 110bhp without DPF.
All was well until it ran out of fuel, although it was showing fuel left, I managed to bleed the fuel system and drain the fuel filter just in case any debris was picked up from the tank and start the car as normal but the error is still present. What could be the issue?

[GiveMeABreak]

Hi and welcome.

It would be worth double checking as there are several variants with and without DPF (PM your VIN and I'll check), You may just need to give it a bit of a blast sown the dual carriageway to get everything cleaned out after running out of fuel. Anyway best to eliminate the DPF as an option first.

[Badtoad66]

PM sent

[GiveMeABreak]

Ok, that VIN is not recognised by Citroen, can you check again. The VIS (last 8 digits) shows this as with a DPF, but I’ll need the complete VIN to check for sure.

[Badtoad66]

Maybe I copied it wrong but I have sent it again. Are there any tell tale signs this car has a dpf that I can check?

[RichardW]

Was this recent? It may well have set a low fuel pressure code when it ran out of fuel. It's possible the light will go out after a number of starts if the fault condition is no longer present. If it's persisted a while, you need to get it on a diag computer to see what it's upset about, and turn the light off.

[Badtoad66]

It was recent, I am more concerned if its a dpf problem but need to know if the car is fitted with one, the VIN suggests not but there is doubt. I am going to fuel the car up and take it for a drive to see if it will clear.

[RichardW]

It's not driving it, it's engine starts - usually about 5 I think. You can tell if it has a DPF - look down the front of the engine, and if it has a DPF there will be a stainless pipe coming out of the CAT/DPF canister about 1/2 way down on the LHS as you look at it (and another one coming from underneath, but that is harder to see) - they then run together up to the driver's side of the engine bay where the pressure sensor is.

[GiveMeABreak]

Maybe I copied it wrong but I have sent it again. Are there any tell tale signs this car has a dpf that I can check?

Ok, that's better.

Confirmed that you do not have a DPF on this variant.
C4 3 DOOR SALOON 1.6 HDi 110 Manual gearbox 5, DV6TED4 WITHOUT FAP.

[Badtoad66]

Thanks Marc, so with that confirmed why would the message come up on a non dpf car? What can be done to sort it.

[GiveMeABreak]

The Depollution System Faulty is a one of those 'generic type' warnings that is letting you know something isn't as it should be. Because of all the contributory issues that can cause the warning, it is important to get it onto a Lexia for a diagnostic so we can identify the code (s). As Richard says, without this we will be guessing. It could be fuelling - related, or emissions related, like the EGR valve for example as just 2 possibilities. There are hundreds of codes that can be returned so it is really a necessity to be able to narrow the fault down.

Even with a fault code, that will help point in the right direction, but fault codes can also be triggered by dependent systems, so becomes a process of elimination.

Have a look here:

viewtopic.php?f=19&t=56452

for members near you and at the bottom of the list is a map showing the locations of members willing to help with a Lexia. Not all are active all the time. Once you have a diagnostic, we may be able to help pinpoint a possible cause.

[Badtoad66]

Thanks I will have a look.

[GiveMeABreak]

I forgot to put the link in - now corrected!

[Badtoad66]

No worries, I plugged in a an ELM 327 OBD and found the errors to be nothing other than fuel pressure faults, quickly cleared them and everything is ok now. Just have another issue to sort out now of low boost under 3000rpm which I think is the vacuum valve but no fauts showing for this.

[GiveMeABreak]

Ok, if they are just temp faults, you should be fine after clearing as you have done - if it is anything more they will get triggered again if it isn't happy. Fingers crossed.