bmw 740ld charging pressure too low

[Nasim51]

Been suffering with a fault with my car. Scan tool says charging pressure control : charging pressure too low. Code 244C00. Also scanned with ista. I have changed exhaust pressure pipe and sensor but still i get the drivetrain message pop up on the motorway when im cruising and when it goes away it drives fine. On manual mode or sports mode its less likely to come up. It only comes up when i ease off the accelerator. Has anyone experienced this issue and if they have fixed it. Car is on 130k miles

[Raimo5]

Check the lines between vacuum distributor, accumulator and wastegate actuator. It looks like wastegates are not closing properly or you have an internal or external pressure leak.

If vacuum control lines are good and no exhaust control management issues are present, then I would do smoke test on engine and exhaust

[Nasim51]

UPDATE

just gave my car in for a diagnostic. At Indytech BMW specialist in romford (UK) Garage carried out investigation for lack of power and done vacuum tests for turbo and control flaps.

SOLUTION

Found inadequate vacuum at turbine control flap. Recommendation to change pressure converter with vacuum box

Was told the access to that part on the engine is a nightmare apparently. Is this true. Has anyone managed to change this easily

Will update if my issue is sorted

[Raimo5]

Originally Posted by Nasim51

Was told the access to that part on the engine is a nightmare apparently. Is this true. Has anyone managed to change this easily

Yes, digging it out is rather involved process and will take hours. There are no shortcuts for changing it as far as I know.

[Nasim51]

Also they mentioned black smoke coming out of the 1st turbo. Is that related to my issue

[Raimo5]

Well there shouldn't be black smoke coming out from any place in car. It can definitely be related to your issue as leaky turbo can cause boost control errors as I mentioned in my first post.

[Nasim51]

Just changed the hose, pressure converter and vacuum reservoir. Engine management light is still on. Will the light clear itself or shal i remove the light with diagnostic. Also do i need reset any sort of adaptations after i changed those parts. Thanks

[Raimo5]

CEL trigger errors must usually be cleared with diagnostic equipment. Most of those codes dont have logistics counter attached to them.

[Nasim51]

Cars boosting perfectly now. Holds boosts litteraly day and night difference after changing those parts. However i noticed theres a whistling noise coming from around the 1st turbo area. Engine management light is still on and is now saying egr cooler. Luckily received the recall letter a few days ago so booked into bmw for that. Hopefully they change it all

[Raimo5]

Not sure if this EGR cooler bypass flap fault will qualify for EGR cooler goodwill campaign. The campaign covers EGR cooler's internal coolant leak into exhaust stream. Then again, if your campaign status is 'open', then they might change the cooler, no questions asked. I recently visited my dealer and they told me I have the campaign open that must be carried out. This campaign entails changing the cooler if inspection of the part uncovers specific fault patterns. For me, they didn't even bother to check the car, but ordered the cooler, which is on few months back order, and will replace once the parts arrive.

Radiator blind error on the other hand also has extended warranty campaign available, so you should check if your car fits inside the warranty parameters.

[Nasim51]

Right so bmw have said its not until 2024 which the revised egr coolers are out and that they highly doubt my fault is related to that. What else can it be. What shal i check or replace