Need some help with an issue I have been having. I have a 2011 bone stock mini cooper clubman S I have bought with 5K miles and now has 106K+. Recently my mini is producing between 5.8-6.5 lbs of boost at max. Once I hit around 6Lbs I can then hear the turbo continue to spool and whine higher, but no additional boost is made. I have visually checked all connections, hoses, clamps, hot and cold side, etc and could not see anything visually. The only issue I found was the intake tube was torn in half at the lower clamp where the rubber stayed when I removed it to inspect the turbo. Not sure that would cause this issue, but will be replacing that. Any thoughts one where I should look? I have no check engine lights, car runs great and as it has always with the exception of the boost issue not going past 6.5lbs. My thoughts are BOV or possible leak on the hot side of the turbo?

Looking for thoughts on what I should look for.

 

Check the diverter valve for a torn diaphragm. Also, if that torn intake tube is on the charged side of the turbo, it needs to be replaced.

 

Replaced the Diverted Valve and that was the issue as many other post made it seem. Question - should I be concerned that the majority of the plastic hat on the diverted was missing? There were peices left but most of it was not in the housing or attached.

 

What made you suspect this problem and/or how did you check the pressure on the turbo? Is this a standard part of the MINI diagnostics?

 

All of the google searches lead to this conclusion. Once I removed it it was clear it was broken from visual inspection. I could feel the boost was down and I have the AeroForce OBDII gauge that shows multiple options with boost being one of them.