DPs Fault 1 hour before MoT.....

[GiveMeABreak]

To me that looks like 2 faults - a permanent one (P11AA) which is the same as your first post on this, and on your top screenshot of the 2 above, there is a temporary fault regarding the open circuit. Is there another fault code? - if not, then that is separate and as it's temporary, it may not generate a code and will clear - but if it becomes permanent, it will likely generate a different fault code.

So with that secondary info, I would double check the electrics.... as if it is intermittently having a supply fault then it might be enough to cause the original P11AA fault.

You might possibly get some more information if you use Diagbox Alasdair.

[xantia_v6]

You would have triggered the O/C fault if you had (previously) switched the ignition on with the valve disconnected. Clear the fault and see if it returns.

[RichardW]

These look like different fault events, as some of the numbers are different:

But the measured pressure is exactly the same to 2 decimal places. Have a look in the live data, and see what it's reading - my guess is you will find it is reading that figure even with the engine off.... I suspect the pressure sensor (or wiring) has had it. As to where it is.....????

[RichardW]

I suspect the pressure sensor (or wiring) has had it. As to where it is.....????

Right on the front of the engine by the looks of it

£95.96 from Citroen mind you.... but available for <£20 from the bay of evil

[GiveMeABreak]

For that reading of 2564.71 milibars (256.47 kilopascals), the voltage of the inlet air pressure sensor should be circa 3.6 to 3.7V.

[Stickyfinger]

OK...Update:

I got the car onto the Lexia ....I found the "Test Actuator" section in the Injection sub section: I tested BOTH the EGR and the Turbo valves.

The Turbo S-Valve when tested "Puffs and releases", any "click" is minimal if at all. (This is true with both the New and the Old (now cleaned) valves. The fault p11AA returned with the New one fitted...

The EGR S-Valve has an audible "Click" but not much "Puff".

I have a MOT booked at 3pm 1500 revs all the way

[Stickyfinger]

MoT PASSED

Now, about this @@@@ing Valve problem !

[RichardW]

Get a look at the live data, and see what that pressure reading is doing is before you do anything else....

[Stickyfinger]

Do I have to that driving or could I do it with just revs......battery in laptop is crap so wlil not last long.

[RichardW]

Start with it stationary, as it's saying permanent fault, it ought to be obvious. But then again...

[KennyW]

At least you have 12 months to find the fault before the next MOT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Kenny

[Stickyfinger]

OK Richard.

Very true Kenny, with no advisory notes either.

[Larsanjus]

Was this one ever solved?

I have the same symptoms on my -08 136HDI (RHR). When accelerating for "longer period" for example joining to a highway, most of the times car goes to limp mode and gives "antipollution fault". Limp mode clears out only by clearing the codes with diagnostic equipment.
Codes are
-P11AA, lack of coherence between control and the measured turbocharging pressure.
-Some cruise/limiter codes, propably caused by the limp mode.
-P2133 and P2131 accelerator pedal hard point switch signal, these are permanent and cant be cleared.

While performing actuator test with diagbox, the control valve clearly releases some vacuum and makes a "puff" noise. This can be repeated maybe about 15 times, then seems like vacuum tank runs out of vacuum if you know what I mean.
I have temporarily removed the (dirty)foam filtel on the end of the hose, maybe a slight improvemet but might also be my imagination.
Battery was quite old and has now been replaced, no improvement on this one, otherwise helped a lot.
Forced regen performed also yesterday, no improvement. Avg regen cycle about 300km.
DPF-life left 17 000km regarding to diagbox. Is this something that could cause similar problems? Would it make sense to empty the filter for test purposes, I am planning to get the car optimized in near future, dpf could be easily removed during that process.
I would just want to get the car working before optimizing.

[Larsanjus]

In my case the problem seems to be (at least so far) damaged and leaking boost pressure sensor.
Found out that some previous owner has broken the sensor plug. Sensor was attached with some gasket sealant but was slightly leaking.
Didnt have new sensor on hand so reinstalled the sensor with sealant and added a cabletie to hold it firmly on place.
So far so good, no fault codes yet with a few days of testdrive.
I'll order new sensor and install it later.