Particle Filter at risk of clogging

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Clarkie89
Donor 2020
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Joined: 04 Nov 2017, 12:09

Particle Filter at risk of clogging

Post by Clarkie89 »

hi all,

I had this warning light come on recently so I bought a diagbox kit from easy diagnostics and have ran a global scan and looked at the DPF data. this is on a 2009 58 plate c5 tourer (x7? thats what works in diagbox anyway)

VIN: VF7**************[VIN obfuscated, can be read by forum staff]

the fault codes that are coming up are;

P1351 - preheating relay circuit; cause = local, status = permanent, fault characterisation = relay supplied and plugs never supplied
P2124 - inlet air heating motorised throttle unit; cause = local, status = intermittent, fault characterisation = open circuit
P1471 - EGR Motorised throttle unit; cause = local, status = intermittent, fault characterisation = open circuit or excessive temperature on an ECU pin
P0243 - turbo pressure electrovalve control; cause = local, status = intermittent, fault characterisation = open circuit or value too high

the Paritcle Emission Filter information is as follows; (temps may be weird as car was only running for a few minutes)

particle emission filter load = 60%
catalytic converter downstream temp = <100 degrees c
total weight of additive contained in the particle filter = 120g
volume of additive remaining in the reservoir = 987ml
exhaust differential pressure = 0 mbar
intake air temp at the airflow sensor = 22 degrees c
inlet air temperature at manifold = 22 degrees c
airflow volume = 22kg/hr
average distance between regens over the last 5 cycles = 282km
distance travelled since last regen = 180km
vehicle speed = 0 (obviously :-D )
engine coolant temp = 58 degrees c
measured injected flow = 6.28mg/impulse
additive adding system fault = addition of additive not possible

60% load seems very high which is odd because I do a lot of reasonably long motorway journeys between 2500 and 3500 rpm so thought that would allow for good regens?
Any help on what could be the root cause? could any of those faults stop the car doing a regen properly or cause the warning light?

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GiveMeABreak
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Re: Particle Filter at risk of clogging

Post by GiveMeABreak »

It looks to be regenerating - so nothing necessarily to worry about at this point -as the distance between regens are within your current average.

The P1351 is a common issue with the glow plugs that are not used as much - so ignore that for now and focus on the other faults.

I can help you with the fault code explanations, but in order to do that please see below:
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Paul-R
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Re: Particle Filter at risk of clogging

Post by Paul-R »

Out of interest what mileage has the X7 done?

admiral51
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Re: Particle Filter at risk of clogging

Post by admiral51 »

Paul-R wrote:
26 Mar 2020, 19:54
Out of interest what mileage has the X7 done?
If i think you are thinking what i am thinking then i guess 100k ish :)

Clarkie89
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Re: Particle Filter at risk of clogging

Post by Clarkie89 »

Thanks Marc,

Paul-R it has done just over 115000, is there something common that goes wrong at that mileage then?

Thanks for the replies

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Paul-R
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Re: Particle Filter at risk of clogging

Post by Paul-R »

Well, if it has done a lot of short(ish) journeys then it will have regenerated more than if it had spent its life up and down the motorways. Each time it regenerates there's a small amount of residue left that doesn't get burnt off and eventually the particle filter will need replacing or, if you are lucky, taking off and cleaning.

That's about the low end of mileage. A car could easily do another 30k - 40k if it's had a different life. The point is that a particle filter is a service item much like a clutch and with a similar sort of life span that can be affected by the way it's been driven.

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GiveMeABreak
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Re: Particle Filter at risk of clogging

Post by GiveMeABreak »

You have several open circuit faults, so a blocked DPF won't account for these - and if the filter was at risk of clogging you would already of had a specific warning message for that "risk of saturation of particle filter (FAP)" or similar. The normal advice for this message is to go for a drive of at least 40MPH for 15 minutes or so and let the engine get hot enough to regenerate.

P1471: Throttle housing electrovalve control (EGR)(Principal air meter) throttle is open. It has been 'Open Circuit' for 200 ms (Air mixer open).

Downgrade modes in effect whilst the fault is active:
  • Inhibiting of the diagnostics and air flow sensor plausibility
  • Cut of all the actuators: EGR butterfly (turbo air cooler), EGR valve and bypass butterfly (inlet air heater) in all functioning modes
Possible Symptoms:
  • Lack of power
  • Jerking/stalling
  • Smoke from the exhaust
Suspect areas:
  • Air mixer
  • Electrical harness
  • Connector
P2141: Motorised throttle housing (Intake air heater ): Open circuit - Throttle open for 1 second.
Downgrade modes in effect whilst the fault is active:
  • Cutting of all the EGR valve actuators (Turbocharger air cooler); EGR valve; Bypass valve (Intake air heater ) In all operating modes
  • Cutting of the butterfly initialisations (Intake air heater )
  • Cutting of the butterfly position regulation loop (Intake air heater )
Suspect Areas:
  • Inlet air heater bypass
  • Electrical harness
P0243:Turbo pressure regulation electrovalve control: Open circuit - Open circuit or value too high for 1 second.

Downgrade modes in effect whilst the fault is active:
  • Cutting of the EGR butterfly (turbo air cooler), EGR valve and bypass butterfly (inlet air heater) in all operating modes
  • Cutting of the "exhaust heat recovery" function
  • The ECU deactivates the programming cycle of the turbo valve
  • Cut in the programming of the stops of the turbo actuator
Possible Symptoms: Lack of Power

Suspect areas:
  • Electrical harness
  • Connector
  • Fuse F20 on fuse box PSF1
  • Turbocharger control solenoid valve
Here's the layout of the fuses in the Engine Fusebox under the bonnet, so as suggested check Fuse F20 first of all:

Image

Clarkie89
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Re: Particle Filter at risk of clogging

Post by Clarkie89 »

Thank you all, especially Marc that is quite the reply. What you reckon should be my first port of call? Check the fuses and a can of contact cleaner to clean up the connections?

I'll have to look at trying to get the dpf cleaned then as I've not had the car long and can't be having it go in to limp mode on me, thanks guys

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GiveMeABreak
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Re: Particle Filter at risk of clogging

Post by GiveMeABreak »

Ok, so there are possibly several issues going on:

1) The particle filter on this engine (DV6TED4) has a life of 75,000 Miles (120,000 KM). The Cerine in the additive system does not get burned in the regeneration process and it is this that eventually clogs the filter. So based on your current mileage, I would suggest it is well passed its life (unless of course the filter has been changed before your ownership).

2) You have a separate additive ECU on this system (EAS200), so this ECU handles the dosing operation of the Eolys additive and not the engine ECU. Now although there is a fault code associated with this not operating - you didn't post that up, so I can't assume this is at fault.

3) You have a Butterfly Double Air Metering Air Doser on this engine, which has 3 functions:
  • Exhaust Gas Recycling (EGR)
  • Help in particle filter regeneration
  • Stopping the engine
DV6TED FAP Air Doser.PNG
ReferenceDesignation
gTurbocharged air (hot air)
hOutput: Turbocharged air to the air/air heat exchanger
jInput: Turbocharged air cooled by the air/air heat exchanger
(24)Inlet air temperature sensor
(25)Inlet air pressure sensor
(26)Inlet air heater throttle (hot air meter)
(27)"EGR" throttle (cold air meter)
So this will help you identify the relevant parts to check the electrical connections.

As for the EGR: the fault code P1471 specifically mentions that one of the pins on the electrical connector is open circuit or too hot:

Here are the pins on the EGR connector plug and the EGR location:
DV6TED FAP EGR Connector.PNG
DV6TED FAP EGR Connector.PNG (45.27 KiB) Viewed 49 times
Channel of the electric EGR electrovalve (1297)signalTerminal to the engine ECU (1320): ConnectorTerminal to the engine ECU (1320): -way
1EGR electrovalve valve position copy sensor supply (5 volts)48-way brownA4
2Actuator (electric motor) (earth)48-way brownD2
3Actuator (electric motor) Open cycle ratio (OCR) (*)48-way brownC2
4EGR electrovalve valve position copy sensor signalGrey 32-wayD4
5EGR electrovalve valve position copy sensor earthGrey 32-wayD3
6Unused--
DV6TED FAP EGR.PNG
(1) is your EGR at the back of the engine and (10) is the EGR Heat Exchanger)

If you suspect it is not regenerating - then try not to drive the vehicle unless essential - as once the filter gets to anything over 70 - 75% full, then regeneration becomes more difficult to impossible and the vehicle will be going into backup mode to limit power.