The actuator's job is to bleed off boost as it builds, not to 'help' boost. It's a valve that is controlled by an electronic solenoid via the ECU that allows engine vacuum into the unit to make it open up, and in turn open the turbo's wastegate to bleed off excessive boost, and hence not allow massive boost pressure to build up and damage the engine or turbo.
Mfr. code: BTA05
X/Ref. 454135-6/
454135-5009S
BRIEF APPLICATION:
Audi A6 2.5 TDI
1999-2005
Part no: BTA05
Stockists