Check engine light came on with an error code: P12a3. Does anyone have any knowledge about this code?

Symptoms: Loud whining whoosing sound around 50 mph, sudden decrease of power. Tick / clack sound coming from rear when idling, possibly from gas tank?

If someone could point me in the right direction so I can start trouble shooting this problem, it would be much appreciated. I'll start by checking all of the hoses, and airbox first.

 

* MINI DTC P12A3 (0x28A5) - Turbocharger Boost Pressure, Minimum Pressure Front of Throttle Valve Implausible
The ECU, in a nutshell, is not seeing the properly spec'ed pressure reading at the throttle body of the intake manifold.
Typically, that's a tall tale sign of a boost leak, where a hose connector, or some other leak has occured.
The turbo is still trying to provide boost, the ECU is reading a much lower value through the MAP sensor and it's seeing a serious discrepancy.
Check all the boost hose connections and complete a pressure check on the entire intake system to verify there are no leaks.

- Erik

 

Well, the error code is definitely turbo related because I just found out that the turbo is dead.

 

Well that just sucks...........

 

Could you provide the exact issue / failure mode with the turbocharger for future searching?

- Erik

 

If I was you, I would remove the oil supply line for the turbo and inspect the banjo bolt along with the line for any clogging or sludge. This line has been known to "clogg up" and when this happens, it of course, damages the turbo bearing.

If you need a walk-through on how to replace the turbo, please pm me, I can help yu with that.
Good luck!

 

This is exactly what happened. There was an issue somewhere with the oil supply line, and it killed the bearing... destroying the turbo. The dealership replaced the turbo under warranty, so that was nice. I was told that I need to keep an eye on the oil level. I found that rather strange, because I check the oil level constantly due to the fact that my Mini burns through so much of it.

There were no warning signs prior to failure of the turbo. It was running just fine the day before. The clicking noise that I though was coming from the rear has not happened again.