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Discussion Starter #1
Hi everyone! Coming to you with a "ghost" problem:
Car: BMW 320d E90 from 2006 - 163hp (engine: M47), manual gearbox

The graph below is the MAF measurements (actual and requested).
The blue line is the actual air mass. The red line is the target air mass.
Does anyone know why is so big the difference between actual/target?
Yes, the car is EGR off (also removed from soft), but this difference in actual/targer air mass existed even before EGR off.
Image link:

The actual air mass goes up to 1350 while the target was about 1030 (all when the car was at about 4000rpm).

Why do I ask you this?
Well, I have a problem with a ghost limpmode: When I floor it and let it rev only up to 3700rpm, everything is ok. When I floor it and let it rev over 4000rpm, then I feel in the seat that the car pushes... pushes ... pushes and suddenly at about 4200rpm it stops pushing (revs still increase, but much slower). After this "procedure", the car limits its power in all gears/rpm and I have to restart the engine to make it work/push well again. Yes, it sounds like a limp mode added by ECU to protect something, but when reading the error codes with Ista-D/Inpa, there is no error code, which makes me think...why a BMW would enter in limp mode with no error code?

What i've checked until now:
The turbo pressure: It is ok, it reaches the ECU requested boost pressure and does not overboost.
The turbo electronic actuator: Tested it with ista-D, it moves very smootly and does not get stuck (so it can't be the turbo's geomethry).
The rail pressure: The actual rail pressure is exactly the same with the requested rail pressure, so there is anough diesel in the rail.
The injectors are also very good (because 2 of them are BOSCH brand new replaced a year ago and the other 2 are in very well condition).
The injection quantity: When the car works/pushes well the injection quantity in kickdown is 80mg/stroke. When it enters in that "limpmode", the injection does not go over 55 mg/stroke.

The only thing that looks strange to me is the air mass (graph above).
Any idea what to check next? Or do you know why my air mass is bigger than the requested value?
Thank you in advance!
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