Charge Air Control Valve

Checking
If the basic boost pressure cannot be adjusted, check as follows:

1 Unhook the exhaust pipe bend from the turbocharger and visually check the flap valve's contact with the turbine housing.
2 Break the seal, remove the circlip and unhook the pushrod from the valve's operating arm.
3 Check that the arm moves easily.
Change the control valve if it is defective.
4 Refit the circlip and affix a seal to the push rod.