[WillLowe]

my car has now been in an out of the garage for 7 weeks (435d) the car was remapped then 2 days later there was no power as if the large turbo wasn't working. I took the car nack to the garage who are a well known company that I and many others have used before, anyway they removed the map back to standard at which time a transmission warning popped up and kept the car in limp mode. From there they replaced the fuel sensor, maf sensor, turbo actuators yet no luck. They then send it off to an automotive electrical company who replaced the boost converter, tested the ECU on a proper rig and the faults cleared.

However on the way home the car has went back into limp mode, this time with new fault codes. Does anyone have any advice on where to go from here judging by the codes below

245A00 hot air mass meter, air flow too low
292100 charging pressure controller for high stage turbo electrical, mechanical or excessive temperature
27B900 exhaust back pressure sensor before turbine exhaust gas pressure too low
244C00 charging pressure control, pressure too low

[Eddamoo]

Did the car drive OK before the codes propped up?

Do you have timings and mileage on the codes? Which one came first?

Finding faults like this is like chicken & egg, whereby the egg is the physical components and the chicken is the sensors in a feedback loop.

[WillLowe]

Annoyingly I havnt got the car infront of me in at work in Liverpool and the cars back home in Newcastle the time stamps don't show on the photos I've been sent either

[WillLowe]

but yeah apparently the car drove fine on the way home. Works fine then the fault code pops up. Quickly turn the engine off and on again and its fine once more for 10mins or so

[exE36M3]

OK, so has there been any work done to the car beforehand?
And of course, what is your year and mileage?

[Firaxis]

Originally Posted by WillLowe

but yeah apparently the car drove fine on the way home. Works fine then the fault code pops up. Quickly turn the engine off and on again and its fine once more for 10mins or so

Sounds like an issue with the mass air flow sensor, issue is I've been down this rabbit hole with a diesel before and it was an utter nightmare. Replaced injectors / glow plugs / MAF / MAP / EGR and in the end it was the intake manifold. So, I know your pain OP diesels are great when they run properly..

Cost a fortune to sort out and it kept popping up with errors for things I thought I'd sorted. If you have DDE / ECU software access you could try resetting the MAF adaptions although I don't have a clue whether or not that would fix it as there's so much else involved.

[WillLowe]

Air flow meter was my first guess but knowing its been changed recently its got me stumped. At this point I feel like driving it into the sea

[Firaxis]

Originally Posted by WillLowe

Air flow meter was my first guess but knowing its been changed recently its got me stumped. At this point I feel like driving it into the sea

If it means anything two of the MAF sensors on my old Alfa were faulty, one was brand new. Again if you can reset the adaptions it's worth a try at least.. If they've replaced the boost converter the errors kinda make sense.