Inadequate air supply to the actuator

Damaged actuator return spring

Replace the actuator. Refer to Engine Brake Replacement .

Damaged actuator piston

Replace the actuator. Refer to Engine Brake Replacement .

Damaged ball joint

Replace the ball joint. Refer to Engine Brake Replacement .

Excessive carbon buildup

1. Remove the exhaust brake. Refer to Engine Brake Replacement .
2. Clean the bore and the butterfly.