[Alchemisty]

Hi all,

Just come back from a 500mile round trip and my engine keeps throwing up a fault and going into a dialled down power mode. As soon as I apply any decent throttle I get a 'drive train fault, drive moderately' warning. The engine has done 56k, runs quiet and clean and when this kicks in aside from reduced power runs and sounds the same, so I'm hoping it's nothing major.

Tonight I cleared the codes, generated the fault and immediately scanned via Carly which threw these up (that came up before):

• 244C00: Boost pressure control, control error, pressure too low/positive deviation

• 27B900: Exhaust gas pressure upstream of the turbine, plausibility: difference measured to the calculated exhaust gas pressure too low

In the past when the error has occurred the faults have referenced the EGR and the swirl flap being too open/closed. Could this be a 'gunked up' issue? As the car spent some time on farmland is and is v dusty under the bonnet. Any suggestions on cause and how i can access the EGR (as I'd like to clean it anyway and whatever swirl flap arrangement it has) for clean running.

[andreigbs]

The first code leads me to believe you have a loss of boost, so either a boost pipe has a leak somewhere (most likely) or the turbo is faulty (less likely).

The second code might be due to the first since it's upstream (or before) the turbo.

I'd look for a split hose or busted boost pipe, or loose connection from airbox to turbo.

[Alchemisty]

Originally Posted by andreigbs

The first code leads me to believe you have a loss of boost, so either a boost pipe has a leak somewhere (most likely) or the turbo is faulty (less likely).

The second code might be due to the first since it's upstream (or before) the turbo.

I'd look for a split hose or busted boost pipe, or loose connection from airbox to turbo.

Thanks dude. Now I've got the engine cover off I can see the airflow direction from the top of the air filter box, across the engine and down into the turbos. I'm presuming both turbos are fed from the same large pipe (initially). Does one sit upstream of the other in sequence? Or are they fed in parallel? As you can tell, my previous 330D engines were single turbos.