Hi all. Car is w210 e270 cdi, om612. 2001 built. The car has put the egr shunt, so the left hand side vaccum pump is disconnected. The catalytic converter after turbocharger exit and near to muffler also taken out. While plugged into star diagnostic system. It detects low boost pressure.. Actual error code I can't remember. When rev up the rpm with neutral/P gear, the turbo actuator seems sluggish or no move at all. While driving the car, can feel the torque is very low.. At 1 to 3rd gear, the car can rev up to 2.5k to 3k rpm with low torque, sometimes the rpm just can't rev pass 2k. Unlike the normal condition, which suppose to feel shoving high torque. Now it feels like a normal natural aspirated petrol car acceleration. Could anyone provide some guidelines on how to check for vaccum leak for turbo actuator? How to DIY map the ecu? Because I felt the also reduced after removing the catalytic converter in the exhaust pipe.