Hi all,

been here before but for some reason locked out of my account and password retrieval not working.

My 2009 Ducato has had several problems over the years but the only engine ones have been the throttle body which caused it to be severely under-powered. I replaced with the new version (Magneti Marelli) and it has been fine since. I did the timing belt about 4 years ago and the engine has had fresh quality oil approx every 6 - 8000 miles, always topped up.

At the last MOT (Nov) I really struggled to get it through the emissions test and it had started to billow black smoke under load. No loss of power or hesitancy, just thick black smoke. I must say the MOT centre were great (depending upon your view of the environment) in that they did the smoke test about 6 times until it passed. This was after taking the inlet manifold off and cleaning it and the throttle body and treating it with 2 different cans of smoke stop and injector clean and thrashing up the motorway in third to warm it right up and let it breathe.

I have checked the intercooler and turbo pipes - they aren't collapsing at high revs and don't appear to have any leaks. I am not sure exactly what sort of noises the EGR solenoid valve should make but I do know that when connected there is a high pitched buzzing noise and the engine has a deeper tone. When you disconnect the right hand pipe from the solenoid valve (looking towards the windscreen) the engine noise loses the deeper tone and the high pitched noise stops. I took it for a test run with both connected and disconnected scenarios and there seems little difference in smoke.

I want to sort this out now and it seems to me there could be several problems. I am about ready for another timing belt change so I thought while I did that I could whip the EGR off and replace it and clean up the heat exchanger, connecting pipes and the throttle body and inlet manifold. I could also replace the intake pressure/temperature sender.Once back together if the problem is not resolved I could then try replacing the solenoid valve. I guess the only other culprit then could be the MAF sensor or Lambda sensor.


I am hoping someone here might be able to add their wisdom and help me here. One question I have is do you think it is worth whipping the head off while I have it stripped down and giving that a good de-coke and a re-grind the valves? The engine has about 110,000 miles on the clock.

I would start with the EGR replacement and then a new MAF sensor. Normally the MAF sensor would make it run like a dog, but it won't hurt to swap anyway.

Hi Peeps. This week I stripped down the front of the engine bay and replaced the EGR, the EGR solenoid and also the intake pressure sensor in the intake manifold. While I was at it I did the timing belt and water pump seeing as I am coming up to 10 years.

I am not sure until I take it on the road whether the amount of smoke has reduced. Hard to tell with it stationary. I do now have an engine fault code however - P0235 - Turbocharger Boost Sensor A Circuit Malfunction

Is this the sensor I replaced in the intake manifold? I am going to check the wiring in a minute but wondered if anybody else has had a problem like this?

Everything seems to be plugged in ok. I have checked the waste gate. the linkage seemed a bit stiff so I undid the linkage and wiggled the gate until it was properly free to open and close and cleaned up the pivot arm.

I still have the P0235 code. I have checked all of the pressurised intake pipes and no leaks. When the engine is revved (stationary) it goes up and down in speed once it hits about 4300rpm - it goes back down to 3500 and then back up again in about a 2 second cycle. Is that just the rev limiter cutting in? The intake pipes expand and release while it is doing that. Does anyone know how to test the waste gate solenoid? or if they are cheap to buy and replace?

Just took it for a test-drive - turbo definitely not kicking in. Otherwise runs ok. Have checked all the wiring, all ok. Can't get my head around it.

Put your old intake pressure sensor back in and see if the fault goes away. If it is a crook sensor, maybe try another one.

That was my thinking - I think I will try a new one. The old one got damaged removing it.

Have you done a proper scan on this or are you just throwing stuff at it? Cheaper in long run to get it properly scanned.

I used MultiECUscan and it said the voltage from that sensor was too high. I used the actuator test in the software to test the throttle valve and EGR valve and they are working ok.

i beleive the sensor in the manifold is the MAP sensor-apparently in the bottom of the manifold where all the gunk from the EGR lands----ours was fully gummed up at the same mileage---added a nice boost in torque when it was all cleaned out with a fresh sensor -
ours had multiple fault codes so ended with new boost sensor and MAF too, although fault was actually MAP sensor- last thing they did was to remove manifold (with 2 broken studs in the process)-pulls really well now -
nightmare trying to find these faults in a garage let alone on the driveway -good maintenance job to get out of the way imo-

Mmmm. Agree. That's why I mapped out my EGR.

oigle said:

Mmmm. Agree. That's why I mapped out my EGR.

Click to expand...

Agree, mapped my one out too, with a bonus of saving 10% fuel ?.