This is a good one,,,we don’t see this to often,,,,F10 2012 N55 engine,,,,check engine light came on 1 time only,,,,fault was turbo over boost,,,,happen at 2600 rpms,,,,,we already replaced the electric pressure control valve which sits next to the valve cover,,,,I performed the turbo boost test,,,,passed test,,,,I smoke tested the turbo and intake system,,,no leak,,,,if there was a leak I would have a low boost fault. I checked the wastewater,,,waste gate is vacuum controlled,,,I checked the waste gate with a vacuum pump,,,,,waste gate working ok,,,,this picture is the electronic blow off valve,,,,we were thinking the blow off valve was hanging up,,,causing the over boost fault. Replacing the blow off valve wasn’t to hard,,,,you just remove the water pump and you have easy access to the blow off valve,,,,just 3 Allen head bolt hold it into place.,,,,this took care of the problem.