C5 filter message

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pete-c5
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C5 filter message

Post by pete-c5 »

Hi there,

l have a C5 2.2 HDI estate 2000 model

it runs fine but every now and then, more so when towing, a warning comes up "unblock deisel filter" and some times its "desiel adertive low",
according to the hand book this should be taken to a dealer (ouch)
any one any ideas how to remedy these faults? are they lincked at all?

thanks pete
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Re: C5 filter message

Post by JohnD »

pete-c5 wrote:
l have a C5 2.2 HDI estate 2000 model

it runs fine but

If you continue to ignore the warnings the engine will go into limp mode. What's needed is for the FAP to be cleaned and the Eolys tank refilled. Do a search - there's loads of information on the forum.
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pete-c5
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Post by pete-c5 »

thanks John

but for my ignorance whats the FAP ?
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Post by Paul-R »

It's the French term for the diesel particulate filter.

Your car is getting on a bit now (sorry) and the residue of the additive in the filter is probably increasing the back pressure so needs cleaning out.

If you do a search for "FAP" here you'll find plenty of threads about this.

As a matter of interest how many miles has it done?
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Post by pete-c5 »

Hi Paul

its just done 60K, and yes that genuine, car has had 2 owners and was a mobility car for the first 3 yrs

am l correct in saying the FAP is just the normal deisel filter or if not what and where is it?, and where is the adertive tank?

l have read several posts on this subject but cant seem to get my head arround it yet, this may be an age related problem (not the cars age)the Fault on my car is not permenent, the dispay comes up with either desiel filter blocked or adertive low, both go out after a short while

one other point, if the car was serviced (as it was at 56K when l bought it) by a none citroen garage could it be possible they did not reset some thing at that time

thanks

pete
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Post by myglaren »

The FAP is located in the exhaust, just ahead of the cat, actually in the same housing.

They should be removed and replaced with a new or reconditioned one. People do clean them themselves but it is technically illegal as the effluent removed is an environmental pollutant.

The Eolys fluid reservoir is adjacent to the fuel tank in the offside wheel arch. Fairly awkward to access.

Some cars do need resetting done with a Lexia - there is another current thread discussing just this issue here.

One thing that affects the blocking of the FAP is how the car is used. Many short trips are the major problem and a trip of a few hundred miles can clear the blockage by raising the temperature to it's maximum and sustaining it while the blocking particles are burned away.

The car may go into 'regeneration mode' on such a trip.
It turns on just about everything electrical to load the engine as much as possible and after a few moments you may feel the engine note change, sometimes alarmingly so, and clouds of smoke appear in the rearview mirror. This is normal and is the rubbish being burned away.

Costs a fair bit in diesel but far more economical than letting the dealer do a 'forced regeneration' - that is no fun at all.
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Post by cachaciero »

60K miles that's getting close to new filter time, assuming it hasnt been changed previously.
If the system has been working correctly and the Eolys never allowed to run out then about now you have a filter which is being clogged up with cerium and no amount of high speed running or forced regeneration is going to clear it.

As Steve says there are many post's on here about replacing / cleaning / even removing the filter.

Personally I would say that initially I was a bit rabid about back washing the filter with a pressure hose and letting the water run into the drains.
However having now discovered that cerium is a naturally occurring substance not particularly toxic if I was faced with the choice of washing my existing filter or paying £200.00 for a new / recond one I think I would give washing a try. (Even though it is technically illegal to let the run of go into the drains ;-)

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Post by KevMayer »

Pete, Take a look at this web site:-

http://www.citroenet.org.uk/passenger-c ... tech3.html
Cheers, Kev

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Post by cachaciero »

pete-c5 wrote: one other point, if the car was serviced (as it was at 56K when l bought it) by a none Citroën garage could it be possible they did not reset some thing at that time
thanks
Pete
That depends on the garage, these cars really require a high degree of specific knowledge to service them, many problems are caused by garages who think that they are the same as every other car. e.g changing the autobox fluid with Dextron 4 just because the majority of auto boxes run on Dextron 4. Filling the hydraulic system with LHM because every Citroen up to C5 used LHM the list goes on.
Most general independents won't have a Lexia just a generic code reader which will not read most of the ECU's on the car. however an independent Citroen specialist may have this equipment.
Like I said depends on your independent :-)

cachaciero
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