Occasionally my 740 turbo wants to die when first started. It can be kept alive by reving and after I have accelerated once up to 40mph it is fine and will run and idle without problem, although it usually has no power for the first few seconds of acceleration. I have replaced or checked everything in the fuel system I can think of: the fuel pump, fuel filter, fuel regulator, mass air flow sensor, coolent temperature sensor, idle control air valve, Jetronic electronic control module, cold start valve, and fuel injectors. On one occasion the RPM indication dropped quickly to zero several times so I checked the timing and found the timing retarded. The car has a distributor but gets its spark from the crankshaft position indicator above the flywheel in the back of the block. I replaced the crankshaft position sensor and the car ran fine for a while but now the problem's back. Is there a common problem with '91 740 turbos that fits these symptoms, and is it most likely fuel or electrical and how can I test for it. Jrip