1993 BMW 740 not moving

1993 BMW 740
195,000 MILES • V8 • 2WD • AUTOMATIC
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SDR08022
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bought this car being told that the reverse seloniod needed to be replaced. when i opened up the tranny by taking of the oi pan i found pieces of metal on bottom and when i took out the vb more meta on top of it. after much debate i decided on used tranny from salvage yard. i just completed the transplant. does not move what could i have done wrong. trans program error and no indicator ight for gear or mode when its on. engine increases rpm slightly when shifted to r or a drive gear but nothing else happens.can anybody suggest any thing
i also put in rebuilt valve body. stomp test shows 1222
Oct 20, 2010 at 9:33 PM
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SERVICE WRITER
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Our local BMW guy has been having pc issues, but he may well stop in. I am not a bmw guy but can still offer support. It is not uncommon to have to study a system as there are so many out there. So.. This car seems to have CAN technology. Controller area Networks. In essence various modules "talk" to each other on data. IF one of the modules drops out, a communication problem occurs and can make an extreme impact.


https://images.2carpros.com/forum/automotive_pictures/30961_bmw1_2.jpg


https://images.2carpros.com/forum/automotive_pictures/30961_bmw_5.jpg

Since communication is critical on this system I would be looking at all connectors being clean, connected and tight. There may be a corrosion problem or simply a connector not connected or connected to a worn connector. Not likely on the latter but I have seen that happen on a few cars. I'll see if I can get you electrical diagrams if you don't have them. Let me know.
Oct 21, 2010 at 6:37 PM
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DOCHAGERTY
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My ears were burning. Did the car drive OK in the forward gears before you did anything? Was the correct fluid installed in the car after the replacement with the known good transmission? Is the seller standing behind the transmission and did it come out of the same production period car? And thanks Service Writer, you can step in on the BMW posts anytime my brother.
Oct 21, 2010 at 8:49 PM
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