My '95 S4S is at a service centre for a C-service and the mechanic (experienced with Esprits) is having an issue with the brakes after a brake system flush. Apparently the caliper on the front right hand side is not operating for reasons unknown (caliper pistons are operational) - car pulls left. He has flushed the system and gotten all the old fluid out. On the master cylinder there are 2 bleeder nipples one of which will squirt fluid under pressure but the other one will only dribble fluid. Has anyone experienced a non-functioning front brake caliper or have ideas why this is happening?