C5 X7 risk of particle filter clogging

[citroenc5mad]

Hi everyone

I got this message come up so popped it to my local garage to sort. The car was showing fault with the glow plugs so had them changed as they seamed a pain in the arse to do myself. Back off the engine block and removing air box etc.

This cleared the fault show and recorded however it didn't delete the message about the risk particle filter clogging.
Having searched this site and read the comments etc. I'm a little lost as the comment were saying this message means that there is already a blockage and no the risk off one.
If this is the case what do I need to do to fix the problem.
As in replace the dpf unit its self. Or just clean it as read mixed opinions about the cleaning and the success in doing this.
Or is it sensors that have gone.

I've had the garage to rescan the car again and still no faults have been found or shown.

Any ideas are gratefully recieved.

Also does anyone know what parameters the car should be read in at the set rev intervals.

Dan

[GiveMeABreak]

Also does anyone know what parameters the car should be read in at the set rev intervals.

Hi Dan - Not sure what you mean here - set rev intervals?

Ok, this is the early warning of the DPF filter starting to clog with soot. If not corrected it will get worse and ultimately may prevent regeneration from being able to take place once it gets to the high 70s early 80s percentage of soot.

If you do lots of short journeys or journeys where the car isn't driving at prolonged periods at operating temperature, then it may not have had opportunities for regeneration to take place or regeneration has been stopped before the cycle has finished.

First thing to do is a drive on a dual carriageway or other de-restricted road in 4th gear for a good 30 minutes or so (once the car is warmed up). You need to keep the revs up and try and get a continuous drive without stopping and starting. That should allow the system to attempt to regenerate.

If this does not clear the error then the soot levels may still be blocking the filter and I would consider getting the DPF cleaned next (this can be done on vehicle by Halfords Auto Centres) a light or deep clean option is available. They open the DPF and use a can of chemical solution that is sprayed into the filter that breaks down the soot. A forced regeneration will then hopefully clear it out for you. It may be an option for you to consider. You don't seem to have had the next more severe message displayed as yet (Service Light on AND 'Risk of Saturation of Particle Filter').

If this clears the error - then do this once a month to prevent the same thing happening again.
Here are some useful links:

Halfords DPF Cleaning

DPF Spray Cleaning

[citroenc5mad]

The guy at the garage said that he has too have a look at the parameters at set rev intervals.

So once the car is warm then open it up for a good 40min drive in 4th should sort the message displayed. Will try this out tomorrow.

What about getting a forced regeneration done would this solve the problem?? But without getting halfords to clean it.
Is it only halfords that has the spray of chemicals too clean them.

My service light is on but it only states the risk off clogging not the saturation message that you mentioned.

Thanks for the reply marc

[GiveMeABreak]

The guy at the garage said that he has too have a look at the parameters at set rev intervals.

So once the car is warm then open it up for a good 40min drive in 4th should sort the message displayed. Will try this out tomorrow.
Yes stick at 2500+rpm if you can to ensure the temperature gets hot enough to sustain a regeneration. Now that you have had your glow plugs replaced this will also help regeneration by helping to increase engine temperature more rapidly - as this is also one of their functions on a Diesel with a DPF

What about getting a forced regeneration done would this solve the problem?? But without getting Halfords to clean it.
It is always better to let the car naturally trigger a regeneration cycle than force one stationary, as this can take a toll on components and the heat generated is excessive without the air cooling you would get whilst driving. Only force a regeneration if really required.

Is it only Halfords that has the spray of chemicals too clean them.
No - these spray kits are available to buy - I just mentioned them as they can do both a light and a deep clean (but I fully understand not wanting any Halfords monkeys to touch my car). If I did ever use them I would insist on being present at all times! There are other places undertaking this service now as it is an affordable alternative in cleaning the DPF rather than a new replacement.

My service light is on but it only states the risk off clogging not the saturation message that you mentioned.
Good, well this is a cautionary message - don't leave it. Try and get something done sooner than later. You may need to go for several of these runs to get a good regeneration done, depending on soot levels.

Thanks for the reply marc

[citroenc5mad]

Perfect marc thanks again soot level was about 20% this morning before giving it a decent burn. Will give a longer burn tomorrow.
Will have a look into these spray kits and give it another good run afterwards.

Thanks for your advise topman

[GiveMeABreak]

Great - best of luck.

[Richard_C]

Just to chip in, all of what has been said before is very sound.

I no longer have a C5, since October, but went from 20k miles to 80k miles in mine. The message that you have happened to me several times - it is just a warning and does go away. It was frustrating - the handbook says to drive at speed - not sure if it mentions rpm or mph - for a period but sometimes the warning came on whilst you were doing just that - on the motorway at 70+ maybe 100 miles into a long trip, for no apparent reason.

Often it would stay on for a 50 or more miles and go out by itself, sometimes it didn't go out but when you restarted after a break (p stop at service area perhaps) it was gone, sometimes it came up twice in one trip, often you could go months between bing-bongs, sometimes it would be on when you arrived home but not there the next morning. I never managed to discern a pattern - I might have expected it of I had been doing short runs for a while but no, it was random.

There is a local filling station I sometimes use - I think they buy their diesel from whatever supplier they can and it is sort of unbranded and maybe it was more likely to complain if I had filled up there but I doubt it - after all it all comes out of the the same few refineries.

I also wondered about the rpm/regen thing. I tried to work out if it was better to use high revs or to use higher gear and heavy right foot, trouble is with the gearing and torque (mine was the 160) its hard to do either without massively exceeding the speed limit.

So my conclusions after all those miles was to channel Bob Marley -

"Don't worry about a thing,
'Cause every little thing gonna be all right."

And it always was

I hope it is for you.

[RichardW]

Get them to check the differential pressure across the filter. This message comes up if the pressure drop is too high; or if regen is incomplete after a few tries (ie short journies back to back). Not unknown for the pressure sensor to turn up its toes and report a high pressure drop when there isn't really - IIRC it reads 128mbar all the time if it's broken. If the soot load is only 20% then it shouldn't be looking to re-gen, which to me suggests the pressure sensor has gone duff.

[DHallworth]

I had this come up on our C5 once as I was on the way home in the early hours of the morning. It happened as I was coming down a slip road onto the M8 in Edinburgh with my foot flat to the floor, high revs and high speeds whilst still accelerating.

I backed off at this point and set the cruise to 73 all the way home other then a long stretch of average speed cameras at 50, I've never seen the message come on again. Presumably the car regenerated itself on the way home and everything was fine.

David.

[Stickyfinger]

My One and only "Risk Warning" came on when I had to floor the go peddle in an emergency within a few minutes of starting on a cold morning....................got to love trucks with misted windows !

It cleared when I got onto the A303 for 15 mins on CC @65

[falling-out-with-my-car]

According to Pleiades my independent the Citroen fap system is way ahead of other makes and the Eolys or blue vadative is supposed to allow regeneration at much lower temperatures so how can the advice to clear the filter out be the same as other makes which use the injection of more diesel into the engine? Surely the cleaning process on a Citroen takes place at lower revs and therefore lower temperatures?

[GiveMeABreak]

Your diesel additive for the DPF / FAP will lower help the temperature needed for regeneration. The Adblue is completely separate and is injected into the catalyst - this process is known as the Selective Catalytic Reduction (SCR) and removes the harmful nitrogen oxide pollutants (NOx) by converting them into water and nitrogen. Once that is done, the exhaust matter travels through to the DPF for elimination of the entrapment and eventual burning of the particulate matter via regeneration. The Adblue systems are generally found on the newer eHDi or blue HDi engines. Although it is another thing to have to top up - it does make them cleaner and meet the Euro 6 emissions requirements.

[citroenc5mad]

I've been driving it hard ring to get it to regeneration. However the light is still on.
I went and spoke to them today after work about getting them to check the sensors etc or them and they are going to do that next week when the car is free as I use it daily for work.

When I was there I said about driving it hard I mean 3000rpm+ in 4th so 70 upwards. I got told this wasn't going to get hotter enough to regenerate.
Which I was surprised about.
He said I really need to run it in 3rd at about 4500rpm which I think is extrem.

I spoke to him regarding the spray as mentioned previously and he said it might work as a quick temporary measure but wouldn't cure the problem.

So am I really not pushing the car enough??

I will mention the pressure sensor readings to him when I pop back there.

Thanks again for all your replies guys.

[GiveMeABreak]

No that sounds VERY extreme and I wouldn't recommend that at all. If it won't cure it at the suggested revs we have mentioned here then it is likely there is another issue. I take it that this is not a Citroen garage you are taking it to? If not, it might be worth taking it to one just to get a proper diagnosis with a lexia. Explain what you have done, but as Richard says 20% soot loading isn't extreme. A proper diagnostic may point to other issues like the EGR or sensors as mentioned.

[citroenc5mad]

It's not a citroen specialist garage.
So I will have to find my local citroen specialist to me for a quite diagnostics check etc.
Thanks again for your help.