Q: Engine fault reduced power

asked by on August 12, 2016

I have a BMW 320d E90 2011. The option was not showing up on the model type. I get an intermittent engine fault running on reduced power message. Took it to get diagnosed and the fault code DTC 4755 showed up mentioning boost pressure actuator. Position control. The mechanic mentioned that the drainage system was blocked and there was moisture in the ECU. Dried it out but the problem persists. Any advice please? 30000 kms not miles.

My car has 30000 miles.
My car has an automatic transmission.

It sounds like you could have a sticking boost pressure actuator. Unfortunately, YourMechanic does not work on your model vehicle. I suggest having the dealership take a look at it.

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