In my 2006 Liberty 2.8 CRD (11.000 km !!) the DTC P0234 comes on every time after driving 4-5 km.
This occurs only at cold wether (below 0 Celsius).
In warm conditions there is no problem.
I checked the vacuum lines (the engine is like brand new), exchanged the pressure sensor at the intake manifold, the rod down to the turbo is also moving correctly with vacuum.
I cleaned the mass flow sensor.
Does anyone have an idea what else I can do ?
My workshop does not.
The MAP Sensor is new, and I disconnected the battery to relearn it.
The turbo hoses are nearly brand new, I could not find any cracks.
I cleaned the MAF with brake cleaner and air-dried it.
All the wiring is also OK - this car ran just 11.000 km in 5 years.
I will try driving without MAF, but I think it will go in limp mode, which my not make sense.
I just came back from test driving with MAF disconnected - you are right, no limp mode, but a little less power.
Unfortunately the P0234 occured again.
It is always at around 1700 rpm and 60-70 km/h with very low gas (gliding) and cold wether.
Under these driving conditions I need nearly no power from the turbo, that`s what I`m not understanding.
This P0234 should be an overboost condition acc to the OBD-Tester I have.
In the Jeep repair manual it`s a low turbo condition - what is true ?
Glad to hear that the MAF disco worked for you. On this side of the pond - many used to do that quite often to bypass the functionality of the EGR prior to the new tunes available to us now from the Green Diesel Engineering (GDE) crew.
To my understanding - that code gets thrown for an overboost situation. And can be a bugger to chase down.
Do a search on here for GDE, and send Kieth a PM and explain your issue. Just possibly they may have better ideas on your issue. I would think you would hear back within a day. Merlintec is another you might PM - he is a master tech based out of the UK I believe.
__________________ 05 TJ RME 42RLE with some things 05 KJ CRD 545RFE, GDE Eco tune, Franky II, Al's 4.5 A-arms, JK Rubi Moabs, Silent Armors 245-70-17's, Spidertrax Adapters, Rola Basket, Fumoto Valve, Pinch welds pounded - Sold 2015
A couple of inches down from the top of the page, it starts with like users CP, the sixth one to the right is the search button & it will give you options on what you want to search for. Unlike some forums, this search actually works pretty decent.
Once you search and find what or whom you are looking for, say GDE - you click on the user name (yours would be Peter59) it will give an option to send a PM (personal message) which will send that person an e-Mail that they have a message. Next time they check EM - they will see that they have a message on JF. Just gives a way to direct contact someone and not use the open forum.