Faulty code P0234

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KennyW
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Faulty code P0234

Post by KennyW »

Hi All,


The above fault code came up after a check with Diagbox.

Clicking on code the following was listed:


Charge pressure regulation
Permanent Fault
Air pressure lower than the settings

along with the following data

Engine speed 2912 RPM
Coolant temp 78 c
Speed 133 KPH or 70 mph
Turbo Pressure reference value 2.53 Bar
Turbo Pressure 2.97 Bar


This occurred during acceleration and changing from 5th to 6th gear.

Cleared fault and has not returned since.

Possible cause small hole in a hose in turbo and related piping.

No obvious change in vehicle performance.

Kenny
C5 x7 2.0 HDi 160 hp Estate exclusive, the newbie
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
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Re: Faulty code P0234

Post by Paul-R »

Is this the X7?
As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

"Trying is the first step towards failure" ~ Homer J Simpson​
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Re: Faulty code P0234

Post by GiveMeABreak »

P0234 - Delphi ECU

Boost pressure regulation: Air pressure above the reference value

Engine speed between 2000 and 3000 rpm - Engine torque below 300 N.m
The measured turbocharged air pressure is 450 mbar above the reference value (For 6 seconds).

Code activated when the following conditions are in force:
- Engine speed above 1500 rpm
- The actual engine torque is higher than 100 Nm

Fault disappearance Conditions: Driving with engine hot for 5 minutes, with several accelerations at full load for 10 s followed by foot-offs.

Back up Modes in effect whilst the fault is active:
  • Deactivation of the request for regeneration of the particle filter from the diagnostic tool
  • Deactivation of the EGR function
  • Cutting of the exhaust heat saver function
  • Prohibition of regenerations of the particle emission filter and stopping of those in progress
  • Deactivation of the kick-down for automatic gearboxes
  • Limitation of performance
  • Request for emergency closing of the turbocharged air cooler by-pass
  • Deactivation of the tight spot for the cruise control
The engine management lamp may be lit along with the 'service' lamp.

Possible Symptoms:
  • Noise
  • Diesel fuel consumption a bit higher
  • Lack of power
  • Engine hesitating, cutting out
  • Smoke from the exhaust
Suspect Areas:
  • Supercharging pressure sensor (Sensor drift ; Connectors ; Electrical harness)
  • Manifold air entry pressure sensor
  • Turbo air cooler by-pass unit
  • Electrovalve of the turbo air cooler by-pass unit
  • Position indicator of the turbocharging air cooler bypass unit
  • Turbocharger
  • Turbocharger electrovalve
  • Position indicator of the turbocharger
Please Don't PM Me For Technical Help

Marc
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KennyW
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Joined: 17 Jan 2006, 21:22
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Xantia 1.9 TD estate
x 132

Re: Faulty code P0234

Post by KennyW »

Thanks Marc,

Yes, it is the X7 Paul

As usual a list of possible fault areas but nothing specific.

Where do you start ?

In the list of symptoms, I have not noticed any of them mentioned.

Kenny
C5 x7 2.0 HDi 160 hp Estate exclusive, the newbie
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
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GiveMeABreak
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C3 1.6 HDi Exclusive Aluminium Grey (The Silver Hornet)
C5 MK II 2.0 HDi Exclusive Obsidian Black
C5 MK I 2.0 HDi SX Wicked Red
Xantia S2 2.0 HDi SX Hermes Red
C15 Romahome White
XM 2.0 Turbo Prestige Emerald Green Pearlescent
XM 2.0 Turbo Prestige Polar White
XM 2.0 SX Polar White
CX 20 Polar White
GS 1220 Geranium Red
CX 2.4 Prestige C-Matic Nevada Beige
GS 1000 Cedreat Yellow
x 5648

Re: Faulty code P0234

Post by GiveMeABreak »

That's the trouble - any one of these can cause the same symptoms - so a matter of either ignoring it and letting the fault develop (if it ever does - may just be temporary) and see if it then triggers any other codes. Easy enough to clear following the guidance though - 10 full load applications , and foot-offs after the engine is up to temp.
Please Don't PM Me For Technical Help

Marc
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KennyW
(Donor 2022)
Posts: 2499
Joined: 17 Jan 2006, 21:22
Location: Letham, Fife
My Cars: Current Citroen's
C5 x7 2010
SWMBO C3 2012
Previous Citroen's
Xantia 2.0 90hp estate
Xantia 1.9 TD estate
x 132

Re: Faulty code P0234

Post by KennyW »

Thanks Marc,

No returned yet.

Kenny
C5 x7 2.0 HDi 160 hp Estate exclusive, the newbie
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
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