On going Turbo pressure problems C5x7 2ltr HDi

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Stickyfinger
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On going Turbo pressure problems C5x7 2ltr HDi

Post by Stickyfinger »

Having replaced with new the Electro Valve I got this today.
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GiveMeABreak
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Re: On going Turbo pressure problems C5x7 2ltr HDi

Post by GiveMeABreak »

Ignore the Cruise Control issue Alasdair - that's the result of a downgrade mode applied due to the other faults:

Here are the code descriptors in more detail - is there a common denominator from your original problem - did you use the correct replacement solenoid valve after all? Did these additional issues occur after replacing it? Some things to think on possibly.

P11AA: Turbocharger pressure regulation solenoid valve control: Incoherence between the command and the measured turbocharging pressure. Incoherence between the position of the turbocharger solenoid valve and the measured turbocharging pressure for 3 seconds: With the engine running, the airflow must be below 40 kg/h compared with the theoretical flow for 3 seconds.

Downgrade Modes:
  • Deactivation of the coherence faults of the flowmeter
  • The ECU stops the regulation of the EGR valve
  • The engine ECU limits the fuel flow
  • Deactivation of the speed limiter
  • Deactivation speed limiter until the next time the ignition is switched on
  • Deactivation of the cruise control
  • Deactivation cruise control until the next time the ignition is switched on
  • The activation of the regeneration of the particle emission filter
  • The ECU stops the regulation of the turbocharger : Change to piloted mode
Consequences:
  • Noise
  • Diesel fuel consumption a bit higher
  • Lack of power
Likely Suspects:
  • Turbocharging pressure sensor
  • Turbocharger position copy sensor
  • Vacuum problem
  • Variable geometry of the turbocharger jammed in the "maximum turbocharging" position.
  • Turbocharger Damaged
  • Turbocharging pressure sensor

P0243: Turbo pressure regulation electrovalve control: Open circuit. Open circuit on the turbo pressure electrovalve for 1s (pressure too low).

Downgrade Modes:
  • Downgrade ASR mode (Torque limitation for traction control)
  • Deactivation of the regeneration by forcing normal mode (No post-treatment or EGR regulation)
Consequences:
  • Lack of power
Suspect Areas:
  • Electrical harness
  • Connector
  • Fuse F20 on fuse box PSF1
  • Turbocharger control solenoid valve
P0234: Turbocharger pressure signal: Pressure too high in relation to the reference value
Negative difference between the turbocharging pressure reference value and the turbocharging pressure measured for 10 s : The pressure measured exceeds the reference value by approximately 100 mbars at high load and approximately 500 mbars at low load.

Downgrade Modes:
  • Inhibits the air flow sensor coherence diagnostics
  • The ECU stops the regulation of the EGR valve
  • Limits the flow of fuel
  • Deactivates the cruise control
  • Limits the speed until the next switching on of the ignition
  • Prohibits the regeneration of the particle filter
  • The ECU stops the regulation of the turbocharger: Change to piloted mode
Consequences:
  • Noise
  • Diesel fuel consumption a bit higher
  • Lack of power
Suspect Areas:
  • Turbocharging pressure sensor
  • Turbocharger position copy sensor
  • Vacuum problem (Excessive vacuum)
  • Variable geometry of the turbocharger jammed in the "maximum turbocharging" position
  • Faulty turbocharger
RichardW
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Re: On going Turbo pressure problems C5x7 2ltr HDi

Post by RichardW »

If you clear the faults, does the permanent one come back right away? If you go into parameter measurement, what does it say about the pressure with the engine off, and then when it's started, and if you rev it up a bit?
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Stickyfinger
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Re: On going Turbo pressure problems C5x7 2ltr HDi

Post by Stickyfinger »

Hi Richard

It will come back when I put load on it (live data at that point is hard as the laptops battery is pants)
I cannot seem to make it "ping" by revving it static.

I will do what I can tomorrow to look into "parameter measurement" and screen shot.