DPs Fault 1 hour before MoT.....

[Stickyfinger]

I quote:

Lack of coherence between the control and the measured turbocharging pressure.

[Stickyfinger]

I am assuming this needs replacing.
Citroen Part No 1618 X2 ELECTRO VALVE 3V
https://www.ebay.co.uk/itm/OEM-Turbo-Pr ... 1906874201

[xantia_v6]

The valve will have a foam filter on the atmospheric port. If this is blocked, you will get over-pressure faults.

[Stickyfinger]

Cheers....Will check that....

I read some say Turbo Vanes sticking...

[RichardW]

That can cause it too, just put the light out and don't rag it to the station and you should get a pass!! Not sure what engine you have got - on the 1.6 Lighty reckoned that if you pushed the actuator down and it didn't spring right back then the vanes were clogged up (which is easy on that engine as it is right on the front!).

[Stickyfinger]

It is the 2ltr 138 with filter....poverty spec engine

[GiveMeABreak]

Not quite poverty spec. better than the 110.....

Fault 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

Symptoms:

• Noise
• Diesel fuel consumption a bit higher
• Lack of power

Suspect Areas:

• 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

So worth checking the sponge filter first to see if that is blocked.

[Stickyfinger]

LOL, it is dark

Where is the valve btw ?

[GiveMeABreak]

Hang on a tick...

[Hell Razor5543]

Tock!

[GiveMeABreak]

Rear of engine Driver side Alasdair. Guide in case you need it..

Usual - Disconnect Battery
Remove the engine style cover

Click images to Zoom

Disconnect the connector (at "a"). CAUTION: On each removal, mark the direction of the vacuum pipes. Uncouple the vacuum pipes (as "b").	Remove: The bolts (2) The turbocharger solenoid valve (1)

Refitting

Refit:

• The turbocharger solenoid valve (1)
• The bolts (2)

CAUTION: When refitting, do not reverse the vacuum pipes .

• Couple up the vacuum pipes ( as "b").
• Connect the connector (at "a").
• Refit the engine style cover .

[xantia_v6]

I see from the drawings above that (like the turbo control solenoid on the THP engines) the filter is remotely mounted on the tube that loops upwards, and on mine, the rubber cover over the filter had shrunk, restricting the flow and causing over-boost errors, simply removing the rubber cover fixed the issue.

[Stickyfinger]

That looks get-at-able

Brill, will look in the morning. If no sign of a problem there I will have the car MOT'd asap and order up one from the web.

[GiveMeABreak]

I’ve got a better diagram of the valve. I’ll put it up when I’m back on my rig.

[GiveMeABreak]

Bear in mind the part you listed above is the EGR solenoid - not the turbo pressure solenoid valve! They have different part numbers...

1618S5 may be the one you want.... part 18

"m" Outlet to boost pressure waste gate (WASTGATE).
"n" Vacuum inlet (via the vacuum pump).
"p" White marking.
"q" Connector.
"r" Atmospheric pressure inlet.