Thread: DEPOLLUTION SYSTEM warning

Hi Danny

Most diesels are fitted with a diesel water sepperator, and they have a drain cock at the bottom of the filter, open the drain cock and drain the sediment out, then prime the system up again, by pumping the little pump on top of the fuel filter, did you change the filter after converting to bio fuel?, you will probably find that the bio has loosened up the gunk in the tank and that has gone into your filter, some vehicles are fitted with a resistance solanoid to notify you that the filter is dirty.

Try that and let me know if it worked for you.

Regards

Alan

Don't know anything about a C4, but "Depollution System" sounds like the Diesel Particulate Filter in the exhaust. This is a matrix grid that heats up and burns off the diesel soot particles in the exhaust for cleaner tailpipe emissions. For this system to work properly, the DPF must get hot, usually by a long drive. Although Biodiesel has lower exhaust gas temps, it is still sufficient to enable the DPF to function, and B30 should pose even less of an issue. Do you make lots of short journeys? Short trips don't allow the DPF to come up to operating temps and for the computer to complete a regeneration cycle. Go for a drive of at least 10-15 min at motorway speeds, and your DPF will right itself.

Could be EGR valve, Peugeot have an issue and I think the engine is the same, also DPF as mentioned, also check fuel filter. A few things ot look at. watch out it does not go into limp mode, that is a nuisance.

Matt

Is this a new C4? Also did the car go into "limp mode"?

BTW, it isn't due to use of bio-D.

I bought a new Peugeot 307 2.0L HDi (engine DW10BTED4), which might be the same as the C4, in Nov 2006, and I had a similar symptom about 6 months after purchase. I had also just filled up with bio-D when it first occurred. The agent didn't seem to have a clue about how to fix it because after two visits back to the shop it was just the same. I had to do my own research and discovered the most likely cause was a faulty exhaust gas pressure sensor - several other owners had similar symptoms which were similar to mine and they had the pressure sensor replaced under warranty. I took it back to the agent and told them I wanted a new sensor fitted and after that the problem disappeared never to return.

Took c4 to citron work shop put on analyzing machine.
Analyzing fault that came up was cold start fault. Told they reset the computer fault did not came up again. But to keep eye on situation. Two day later fault reappeared. But the car was not even cold. Rang up, they said bring car for more test. But most properly, a faulty sensor. I have stop using bio-D for now. So if there anybody out there who does use it on this particular engine 2.0L HDi lets as know as am not very confidant at the moment.
But I still use bio-D on work vehicle

Thank you for your useful comments and keep them coming.
Mr. English

It was exactly the same on my 307 (which I am certain has identical engine to your C4). I even had the fuel tested when the De-pollution warning came up on mine. It was according to diesel specs and not the cause of the problem. Your problem is highly unlikely associated with using bio-D.

In my experience, Peugeot/Citroen dealers are not very competent at diagnosing faults at all. They simply do not know how to interpret the "real" cause of the fault codes they read from the analyser.

On my first return to dealer after the warning came up, they simply reset the computer and said "try it again". Within 2 days it came up again so I took it back. Reset the computer again and within a week back came the fault warning. This time I did my own research and after some questioning of other owners who had similar problems I came to the conclusion that the exhaust pressure sensor was the most likely cause. I insisted they change it and they did. Result - no more problems.

Here is the thread for the most convincing saga which convinced me http://www.aussiefrogs.com/forum/showthread.php?t=42958