my fap filter is missing ..HELP PLEASE !!

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reef2k
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my fap filter is missing ..HELP PLEASE !!

Post by reef2k »

bought a C5 non-runner,fitted recon injectors which got it running. diagnostics said particulate filter was blocked,so just removed the whole stainless steel box from below the flexible down pipe ,opened it up and ...nothing, its empty.should this box contain cat and fap ? will the car run without any of these ? i do less than 5k a year,so is there any bodge that'll work ok,money is very tight,so dont want to spend much more on it. i also understand i will probably have to replace the ECU and get it reset by citroen ? would appreciate any help guys, regards Nick
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AndersDK
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Post by AndersDK »

Hi -

Whats the build year of this C5 ?
IIRC its quite common that UK cars where not fitted with cat and fap until something up to 2004 (correct me please).
Or simply may have been removed as not required for MOT before this bulid year.
Meaning less parts to replace as emissions regulations are not that tight until this buildyear.
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Post by reef2k »

hi anders,
its a 2002 2.2hdi .i think the cat is on the downpipe,but the housing for the fap is empty,and should definitly have one,but its been removed for some reason, regards Nick
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Post by JohnD »

Not 100% sure but I think the 2.2 had the particle filter right from the start whereas the 2ltr didn't get one until 2004 or so.
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Post by cachaciero »

The 2.2 had the FAP filter fitted from day one (2001).

The CAT bolts onto the down pipe is cone shaped at the front and has a square flange at the back the FAP filter fits on the back of the cat, bolted on to the square flange with four bolts.

The way the ECU detects that the filter is blocked is by measuring the differential pressure across the FAP, I would have thought that if everything else was there and working it would not know that the FAP element was missing as the diff pressure would be minimal.
If diagnostics say the filter is blocked then I would suggest that the two small diameter pipes from the FAP back to the pressure sensors are not connected or there is a problem with the pressure sensors.
You would still have to have the EOLYS tank filled with something (diesel) otherwise the system will keep complaining about low additive levels.

As far as I can see there should be about a +3BHP increase without the FAP filter at the expense of increased black smoke out the back.

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Post by AndersDK »

cachaciero wrote:The 2.2 had the FAP filter fitted from day one (2001).

The CAT bolts onto the down pipe is cone shaped at the front and has a square flange at the back the FAP filter fits on the back of the cat, bolted on to the square flange with four bolts.

The way the ECU detects that the filter is blocked is by measuring the differential pressure across the FAP, I would have thought that if everything else was there and working it would not know that the FAP element was missing as the diff pressure would be minimal.
If diagnostics say the filter is blocked then I would suggest that the two small diameter pipes from the FAP back to the pressure sensors are not connected or there is a problem with the pressure sensors.
You would still have to have the EOLYS tank filled with something (diesel) otherwise the system will keep complaining about low additive levels.

As far as I can see there should be about a +3BHP increase without the FAP filter at the expense of increased black smoke out the back.

cachaciero
Great explanation cachaciero - thanx 8)

But is it required for MOT ?
Could it be that the previous owner found out it was not required and decided to go for that few extra horses ?
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Post by cachaciero »

AndersDK wrote:
cachaciero wrote:The 2.2 had the FAP filter fitted from day one (2001).
big snip-----

As far as I can see there should be about a +3BHP increase without the FAP filter at the expense of increased black smoke out the back.

cachaciero
Great explanation cachaciero - thanx 8)

But is it required for MOT ?
Could it be that the previous owner found out it was not required and decided to go for that few extra horses ?
MOT? Probably not if it can meet the smoke and emissions test, the examiner is not going to take the FAP apart to see if it has an element in it or not BUT----------.

It does represent a material and major change in the anti pollution system which the motor has been certified with, not sure of the legal position but if this was discovered by the taxation authorities I guess they may be able to make a case of fraud in that the motor is emitting more carbon than the tax bracket it's in.
Whatever, my gut feel is that in the admittedly unlikely event of an in depth investigation by "authority" then there is the strong possibility of "legal pain" and if not by them then the insurance company who would surely take issue with an un-notified modification particularly one which has increased the rated engine power.

The person that removed the core of the filter almost certainly did so for reasons of cost, a replacement FAP is anywhere between £175 and £400 plus what another £100 or so for EOLYS he only did what I suspect many of us with this system have thought about doing.

As far as this particular car is concerned I get the feeling that it has suffered from lack of maintenance and that which has been done has been done on the cheap as a result it is likely to be an even bigger money pit than the average.

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Post by AndersDK »

:shock:
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Post by KevMayer »

Hello chaps,

When I tax my C5 2.2 Hdi I don't think the tax man has made any allowance at all for the fact that I have a FAP and am keeping my emissions really low.
I think I pay the full wack of yearly tax for it. So I don't see any tax implications in removing the FAP. What I want to know is will the C5 work ok without it and will the ECU give you full power or just limp home mode ?

I can't see any insurance company getting excited about a slight gain in BHP. They don't give you a refund either if your car is running badly. That would be worth trying eh ?

I remember asking a question some time ago about running without the FAP and Wheeler told us that the pressure differential system across the FAP has to see a minimum pressure otherwise it suspects that the FAP has been removed and throws up an alarm.

I'm very interested to know what the effects are of running without a FAP. Do you get better mpg for instance ?
Cheers, Kev

02 plate C5 2.2 Hdi Exclusive SE (now 170k miles 03/21).

Used to have:- Xantia 1.9 TurboD SX. 1996 Blue & 1998 Silver Activa. + 1992 BX TZD Turbo.
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Post by cachaciero »

KevMayer wrote:Hello chaps,

When I tax my C5 2.2 Hdi I don't think the tax man has made any allowance at all for the fact that I have a FAP and am keeping my emissions really low.
I think I pay the full wack of yearly tax for it. So I don't see any tax implications in removing the FAP. What I want to know is will the C5 work ok without it and will the ECU give you full power or just limp home mode ?

I can't see any insurance company getting excited about a slight gain in BHP. They don't give you a refund either if your car is running badly. That would be worth trying eh ?

I remember asking a question some time ago about running without the FAP and Wheeler told us that the pressure differential system across the FAP has to see a minimum pressure otherwise it suspects that the FAP has been removed and throws up an alarm.

I'm very interested to know what the effects are of running without a FAP. Do you get better mpg for instance ?
Hi Kev

These days car tax is based upon certified carbon emission this engine is certified with the FAP so the taxman HAS taken this into account, no FAP means higher carbon emission which means you should pay more tax, not you understand my logic but certainly the logic of the morons that tax and rule us :-(

Insurance companies will in the event of an accident get excited about any performance enhancing modification that they discover and that has not been declared to them and likely refuse to pay out because of it.

Interesting point about the minimum diff pressure I did wonder about that but currently on my car which has a relatively new FAP the Lexia says the diff pressure is zero and there are no warnings. Of course it maybe that the Lexia looks for an offset in absolute terms which it equates to zero. If a diff pressure is required shouldn't be too difficult to stuff a bit of restriction into the empty FAP filter case.

As to running without a FAP I have no experience but the power rating difference for the early 2.0ltr which was supplied both with and without FAP was about 2 BHP so an increase to 3 on the 2.2 doesn't seem unrealistic. This must come about because the engine is doing less work to push the exhaust i.e increase of efficiency so I guess that would translate into slightly reduced consumption.

Sounds like you are very tempted to go this route would be interested in the results if you do :-)

cachaciero
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Post by RichardW »

FAP has nothing to do with carbon emissons - it is there purely to catch soot particles. In fact it is likely that the use of the FAP increases the carbon emissions, since it gives extra back pressure in the exhaust system, and requires additional fuel to burn the soot off (and more fuel = more CO2!). Of course, there wouldn't have been a regen of the FAP during the official consumption test, so the extra fuel required wouldn't figure in the 'offical' consumption figures :twisted:

A modern CR diesel will easily pass the MOT emissions test (which for diesels is smoke opacity only) without a FAP, unless it is very very poorly. There is still no direct requirement for a CAT or FAP on a diesel - althought they are more commonplace to meet the NOX and particulate requierments of the current Euro emissions standards. It might not strictly meet the letter ofthe type approval, but AFAIK there is no back check against removing a CAT or FAP. Whether you concience supports it is another matter.

I agree that a non running 2.2 HDi, however cheap, was possibly not the best choice if you're short of cash..... :?
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Post by Penguin »

cachaciero wrote:Hi Kev

These days car tax is based upon certified carbon emission this engine is certified with the FAP so the taxman HAS taken this into account, no FAP means higher carbon emission which means you should pay more tax, not you understand my logic but certainly the logic of the morons that tax and rule us :-(
Is that true of a car of this age? Both of my cars are older than this (95 & 98 ) and I am taxed on engine size NOT carbon emmissions. I can't remember offhand at what age of car the carbon emission ratings take over from engine size ratings.
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Post by cachaciero »

Penguin wrote:
cachaciero wrote:Hi Kev

These days car tax is based upon certified carbon emission this engine is certified with
-----snip--]
Is that true of a car of this age? Both of my cars are older than this (95 & 98 ) and I am taxed on engine size NOT carbon emmissions. I can't remember offhand at what age of car the carbon emission ratings take over from engine size ratings.
Hi Penguin

Not absolutely sure of date but I am pretty sure it coincided with the date of the introduction of the new registration plate which was as I remember 2000 /2001after which all new cars had to have a certified carbon emissions statement from the manufacturer upon which now to some extent VED is based.

One reason why a late (1999/2000) XM in good nick has become a very desirable motor, in my eyes at least.

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Post by RichardW »

CO2 based emissions from 01/03/2000 - eg Y plate and later. My Xantia HDi misses out by 4 weeks, having been registered on 31/01/00 - would be £60 a year cheaper if it was on CO2 based :roll:
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Post by reef2k »

Hi guys,
many thanks for your replies,its much appreciated, but my original question was if the car will run ok without the fap in line. based on the info you've given me, im happy to do so, but will the ecu sense this and will i need to replace the ecu as ive read this may be the case. any definitive answers please !! the car is in limp mode at the moment, so is'nt drivable. regards Nick
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