leaky waste gate actuator

[joesushi]

My friend just bought this car 2 months and has been doing preventitive maintenance ever since. His car has had a knocking issue ever since he's bought it. Would he be over boosting? would the diaphragm in teh actuator be actuating at higher boosts due to a leak in it? this would account for the knocking, running high boost and really lean. I guess we're gonna be looking for an actuator now. To answer your question its leaking right where the shaft leaves the actuator.