Back in the old Eseries days, the classic symptoms were a hot day, air conditioning + braking + power steering pump active ===> stall. Typically when you were braking up to a corner. Not the best place for it to happen. Idle hunting when stopped was another symptom. In the ESeries, the typical problem was the ICS (Idle Control Solenoid) and/or dirty throttle body. The fix was to clean the throttle body and give the ICS a WD-40 bath, or replace the ICS. I guess in the new fangled days, the TPS has taken over the role of the ICS... I wouldn't know a TPS if I fell over one, but how much are they to replace? Could you actually give one a nasty spray with WD-40 getting the WD-40 all in it which might 'ungunk' it, or is it all electronic bits? Might save someone a buck or 2... ws