Citroen C5 DPF power issue, many trips to garage, please help!

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Sloppysod
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Re: Citroen C5 DPF power issue, many trips to garage, please help!

Post by Sloppysod »

Just a thought
If the Dpf is blocked, ie too much back pressure, then surely this would then reduce the amount of vacuum provided by the engine. So, a clean free flowing exhaust system would help! And as the Dpf will eventually need cleaning, would it not help with the diagnosis to get it cleaned first. I agree that not using the car too much until all faults are permanently cleared would be a good idea.
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Re: Citroen C5 DPF power issue, many trips to garage, please help!

Post by GiveMeABreak »

I'm not sure I get where you are coming from Stu - the vacuum pump is driven off the engine and is split into the primary circuit for braking and the secondary circuit for the engine functions. So the vacuum for the various electrovalve operations shouldn't have anything to do with the DPF blockage. The engine will keep running and providing a vacuum, so shouldn't be affected by the DPF even if blocked. Or have I lost the plot? :-D
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Re: Citroen C5 DPF power issue, many trips to garage, please help!

Post by Sloppysod »

Sorry, did not realise there was a seperate vacuum pump, I thought, obviously wrong, that the vacuum was provided by the inlet pressure, like the old days...................
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Re: Citroen C5 DPF power issue, many trips to garage, please help!

Post by GiveMeABreak »

Here's the vacuum pump in the first pic - and again in relation to the EGR circuit
Brake Vacuum Pump.PNG
Brake Vacuum Pump in EGR Circuit.PNG
PeetSK
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Re: Citroen C5 DPF power issue, many trips to garage, please help!

Post by PeetSK »

GiveMeABreak wrote:
03 Jun 2019, 14:26
Understand what you are saying, it's just this is a specific combo of specific codes that has occurred for which we know there is a specific issue with. The main issues are with the electrovalves and these are not related to the fuel. If there was a blockage there would be issues relating to fuel rail pressure and injection faults - which there are none.

I'm in the process of getting the TSB for this, so will have a better idea of the problem (I hope) shortly.
Hi Marc,

I have similar issue as stated in here, but so far have only P0488 and P1498 codes. Did you get your hands on that particular bulletin? Ii would be great to check for my car as well.

Thank you
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Re: Citroen C5 DPF power issue, many trips to garage, please help!

Post by GiveMeABreak »

You have a different vehicle and although the engines may be similar, there could be differences, especially with the hybrid.

Pop your VIN up and I'll see if there are differences as they relate to your specific engine.
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Re: Citroen C5 DPF power issue, many trips to garage, please help!

Post by PeetSK »

PM with VIN sent. Much appreciated
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Re: Citroen C5 DPF power issue, many trips to garage, please help!

Post by GiveMeABreak »

Ok, so the fault codes on the previous page are relevant to your vehicle.

You may get the illumination of the engine warning light with or without a loss of power.

The issues relate to the Air Mixer.

There is a Technical Bulletin for where one or more of these fault codes exists on this engine that necessitates a check of the Air mixer control rod.

If the control rod is uncoupled, then the repair is to replace the Air Mixer, the Air Mixer Solenoid Valve and also the Vacuum pipe between the 2. If the control rod is not uncoupled, then more troubleshooting is required and the specific replacement of these components is not required.
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Re: Citroen C5 DPF power issue, many trips to garage, please help!

Post by PeetSK »

Finally I am getting somewhere. I already replaced: whole EGR, DPF cleaned and MAF sensor and nothing helped. Do you have at your disposal this mentioned Bulletin? Some graphic diagram would be reallyhelpful, so I wont replace or check anything else :) or the one what you already posted is fine? thank you

Currently there is no power loss.
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Re: Citroen C5 DPF power issue, many trips to garage, please help!

Post by GiveMeABreak »

There are no diagrams in the technical bulletin, but I can have put something up regarding the air mixer removal / refitting tomorrow for you if needed.
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Re: Citroen C5 DPF power issue, many trips to garage, please help!

Post by PeetSK »

Sounds very good. It would be really helpful.
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Re: Citroen C5 DPF power issue, many trips to garage, please help!

Post by GiveMeABreak »

Hi Peter

Sorry this was a bit late - I completely forgot.

Removal / Refitting of Air Mixer: Peugeot 508 RHX DW10CTED4 with Hybrid Traction System.

Removal

Disconnect the ancillaries battery (BSI Reset / Battery Disconnect / Reconnect Procedure)
Remove the engine style cover.
Pete A.PNG
A Single metering unit.
B Double mixer.
CAUTION: Protect the engine cooling radiator to prevent damage to the fins.

Unplug using a thin screwdriver:
  • The inlet air mixer sensors (at "a")
  • The inlet air pressure/temperature sensor (at "b")
Release and move aside the electrical harness (1).
Uncouple the air inlet union (2).
Pete B.PNG
Pete C.PNG
Uncouple the vacuum pipes (3) (at "c").
Unfasten and move aside the vacuum pipes (3).
Slacken the mountings (4) sufficiently to allow lateral movement of the support (5).
Pete D.PNG
Remove:
  • The bolts (6)
  • The bolts (7)
  • The inlet air metering unit (8)
Refitting

Adhere to the Tightening Torques below:
Pete F Torques.PNG
ReferenceDesignationTightening torque
(1)bolts (Inlet air metering unit )0,8 daNm
(2)bolts ( intake air distributor) (*) (**)1 daNm
(3)Fasteners (Piloting electrovalves )0,65 daNm
(4)nut (Exhaust gas recirculation heat exchanger )2 daNm
-Stud (Exhaust gas recirculation heat exchanger )0,6 daNm
(5)nut (Exhaust gas recycling valve)0,8 daNm
-Stud (Exhaust gas recycling valve)0,4 daNm
(6)bolts (Exhaust gas recycling valve)0,8 daNm
(7)Stud (Exhaust gas recycling valve)1 daNm
(8)bolts (Exhaust gas recycling duct)0,8 daNm
(9)nut (Inlet air metering unit support)0,8 daNm
(10)bolts (Inlet air metering unit support)2 daNm
(11)bolts (Inlet air metering unit )0,8 daNm
(12)nut (Inlet air metering unit support)2 daNm
(13)Stud (Inlet air metering unit support)0,6 daNm
(*) Follow the tightening sequence (**) Follow the tightening procedure
Pete E.PNG
CAUTION: Check the condition of the seal (9); Exchange it if necessary.
Position:
  • The seal (9) on the inlet air mixer unit (8)
  • The inlet air metering unit (8)
Tightening procedure: Assembly of inlet air mixer control unit (8) and its mounting (5):
  • Tighten the mountings (4) by hand; The support (5) must be properly seated, allowing lateral movement
  • Tighten the bolts (7) to torque
  • Tighten the bolts (6) to torque
  • Tighten the mountings (4) to the specified torque
Couple up:
  • The vacuum pipes (3) (at "c")
  • The inlet air union (2)
Clip in place:
  • The vacuum pipes (3)
  • The electrical harness (1)
Connect:
  • The inlet air mixer sensors (at "a")
  • The inlet air pressure/temperature sensor (at "b")
CAUTION: Remove the protection on the cooling radiator.
Refit the engine style cover.
Reconnect the ancillaries battery following the reconnection part of the (BSI Reset / Battery Disconnect / Reconnect Procedure)

CAUTION: Perform the operations to be carried out following reconnection of the battery. See Guide above.
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Re: Citroen C5 DPF power issue, many trips to garage, please help!

Post by PeetSK »

Thank you Marc for detailed assembly / disassembly - checking everything.