Adjusting Basic Charging Pressure

To remove







IMPORTANT
The basic charging pressure is the starting point for the Trionic system's pressure control function and must be adjusted correctly.


1 Undo the lock nut on the end piece and break the seal.
2 Remove the locking ring and unhook the pushrod from the wastegate arm (step 2 is easier to carry out from below). Use special tool 83 94 538.
3 Adjust the basic charging pressure by screwing in the end piece to increase it or screwing out to decrease it. Screwing the end piece 1 turn will change the basic charging pressure approx. 0.02 bar.







IMPORTANT
The wastegate must never be "pretensioned" more than 2 mm (2 turns), even it the basic charging pressure cannot be adjusted to within 0.40 ± 0.03 bar


To fit







1 Attach the pushrod to the arm and tit the locking ring.
2 Check the basic charging pressure on a road test, see Service Manual "2:4 Exhaust system, Cooling system, Turbo system", "Checking boost pressure (on the road)". If the basic charging pressure cannot be adjusted, see Service Manual "2:4 Exhaust system, Cooling system, Turbo system", "Wastegate valve, turbo pressure" and "Diaphragm box".
3 Seal the pushrod.