2009 Berlingo Van 1.6 Diesel P2034

[malc2003]

Hi!  I hope you guys can point me in the right direction to try and resolve an issue I have with my 2009 Berlingo Van, it throws up error code P0234 and occasionally P0238.  Goes into limp mode adn wont come out of it without resetting the code.  This happens at motorway speed every time or any hard acceleration.  

I looked through some posts related to this code and found it may be the turbo solenoid, but I cant find an image of where that is located/what it looks like.  I googled the part but i'm not sure where to start looking, am I correct in thinking its hidden at the back of the engine?  Can I get to it from underneath or do I need to strip away a load of gubbins from on top to get to it?

Thanks in advance and any other advice is welcomed!

[malc2003]

Not sure if these images will upload but that’s the engine

Edit - no they didn’t!

This is the link to the images:

https://ibb.co/2d0kBN2

https://ibb.co/zsKB3kG

[Sol]

Those codes don't mean anything in the official lists of codes, where did you get them from, a generic code reader?

Here is the replacement procedure from Citroen for the turbo electrovalve, it is right down behind the engine by the look of it.

Did you mean P0234 and not P2034? These would then likely be over-boost, maybe also caused by a bad diaphragm on a vacuum operated wastegate or something.

P0234 Turbocharger pressure signal : Pressure too high in relation to the reference value
P0235 Turbocharger pressure signal : Invalid signal
P0237 Turbocharger pressure signal : Short circuit to earth
P0238 Turbocharger pressure signal : Short-circuit to positive
P0243 Turbo pressure regulation electrovalve control : Open circuit
P0245 Turbo pressure regulation electrovalve control : Short circuit to earth
P0246 Turbo pressure regulation electrovalve control : Short-circuit to positive

[malc2003]

Sorry! I just edited it because I rushed the numbers, it is P0234 and on occasion P0238

[malc2003]

Thank you so much for the instructions! I’m not sure it’s that I’m just going off what others have found with that same code so anything else to check that’s less invasive first would be appreciated! the waste gate does move, and I’ve take the pipe off it and with the engine running there is vacuum/suction against my finger.

[Sol]

It sounds like it should be working then, and no worries about the numbers, it happens a lot. Check the wastegate is open - and closed - when it should be. It may not move enough. You will see the Turbo pressure sensor on the document regarding "check the turbo pressure" - this may be clogged with sooty crap, or simply failed too.

Especially since the P0238 is "turbo pressure signal - short circuit to positive" - this sensor would be easy to change out. I would try that before tackling the electrovalve, which must be actually working if you get vacuum to the wastegate tube when required.

Here is all of the documentation I have on the turbo procedures, may help in the meantime:

[malc2003]

Ok I messed up again (it’s been a long day) I haven’t checked to see if there’s vacuum in the pipe with the engine running at all, I put my finger on the waste gate connection and when I moved that by hand it has a vacuum effect on my finger. I’ll take a look at the gate movement properly when I have another pair of eyes with me tomorrow…..is the turbo pressure sensor called the MAP sensor? Thanks again!

[Sol]

Ok good choice. Best to check if there is vacuum there - which would prove the solenoid is ok. Pretty sure the wastegate should move when the engine is started and move back when switched off. Getting boost to build when sitting still is nigh on impossible. Maybe the basic small movement from startup to shutdown would show if it's working.

Alternatively get a vGate iCar Bluetooth adaptor from Amazon or eBay, then get the app called "car scanner" or "torque pro" and as well as getting fault codes yourself, you can see actual boost pressure when driving or revving the engine. I think max should be 1.2 bar or 18 psi, someone may correct that, going from memory there.

And yep, it's the map sensor, Citroen just refer to it as turbo pressure sensor but they're the same thing. It should be on the pipe leading from the intercooler to the engine intake. (After the intercooler, left side pipe)

[malc2003]

Thanks so much, I’ll remove the sensor and inspect tomorrow. Other than any build up it’s probably not possible to tell if it’s working but once I have eyes on it I’ll be able to get a replacement with confidence if it looks suspect. I’ll ask take a look at the vGate thing now too.

[malc2003]

Is this one correct?

https://www.ebay.co.uk/itm/324011557011?...media=COPY

I also seem to have an issue with the OBD port, my simple scanner only works with it on an angle when I’m holding onto it with one leg out of the door and a hat on so I’ll need to check the pins for that.