My 1994 850 Turbo has 102K miles. I have owned it since 36K and have followed all service intervals including tranny fluid changes. The tranny has always worked correctly. Last week I installed a modified ecu similar to IPDs and drove about 1K miles. The engine and tranny performed cirrectly. I then removed the modified ecu and reinstalled the stock ecu. The very next time that I drove the car the tranny was holding each gear too long and shifting much firmer! All the electronics of the tranny seem to be working correctly. In econ mode the tranny holds the gear less time and shifts less firm. The tranny will also start in 2nd gear in winter mode. I removed both the engine ecu and the tranny ecu and reinstalled them without any change. I then disconnected the battery for a few hours hoping to reset both ecus but not change also. The tranny acts like it has a very aggressive shift kit. It is very throttle sensitive and will downshift at the slightest increase in throttle. Could the failure and ecu switch be a coincidence? I don't have the modded ecu to reinstall to test. Any ideas?
Thanks,
Todd
1994 850 Turbo Wagon
1982 BMW 745i Turbo
1985 M535i