C4 2.0 Diesel Engine Issues

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gosnoid72
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Joined: 25 Apr 2022, 21:43

C4 2.0 Diesel Engine Issues

Post by gosnoid72 »

54 plate 2.0 VTS Diesel. Symptoms.

'Depollution Fault' message on dash.
Sluggish performance - turbo doesn't seem to kick in until about 3000RPM
Black soot over the boot after a recent long motorway journey.
Codes P0299 and P2565 from a basic OBD reader.

Does this immediately strike a note with anyone?
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GiveMeABreak
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Re: C4 2.0 Diesel Engine Issues

Post by GiveMeABreak »

P0299 - Turbocharger pressure signal: Pressure too low in relation to the reference value. Difference negative for 10 seconds, between the turbo pressure reference and the measured turbo pressure.

Possible causes:
  • Air meter restricted
  • Clogged air filter
  • Obstacle obstructing the air passage
  • Air lock between compressor and engine
  • Turbocharging pressure sensor
  • Turbocharger position copy sensor
  • Vacuum problem
  • Variable geometry of the turbocharger jammed in the "minimum turbo" position
  • Faulty turbocharger
P2565 - Turbocharger position copy signal: Voltage above the maximum threshold. Voltage higher than 4,95 V for more than 5 seconds.

Possible causes:
  • Turbocharger position copy sensor
  • Electrical harness
  • Connector
Given that the Turbo Position Copy sensor seems to be common between the 2 faults - it may be a place to start.
gosnoid72
Posts: 22
Joined: 25 Apr 2022, 21:43

Re: C4 2.0 Diesel Engine Issues

Post by gosnoid72 »

Sounds like the logical next step. I believe its a bit of a pig to change? Any idea how I know what part to order prior to me getting underneath it?
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GiveMeABreak
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Re: C4 2.0 Diesel Engine Issues

Post by GiveMeABreak »

Citroen no longer sell the position sensor part which they charged about £200 for when it was available, but you should be able to get one on the aftermarket. I think the sensor part alone is over £100 for a Garret one and this fits into the capsule module.

But I would suggest you make doubly sure this is the case first of all as fault codes can only point to possibilities. I'd suggest getting the fault diagnosis confirmed first before spending out.
gosnoid72
Posts: 22
Joined: 25 Apr 2022, 21:43

Re: C4 2.0 Diesel Engine Issues

Post by gosnoid72 »

Thanks. It's going in for the depollution tank soon, so I'll get them to do some investigation.