BMW Repair: 94 BMW 740 E32 AC/Heat/Fan problem, bmw 740, heat fan

Question
Don, I need your help.  The defrost and fan only comes on at random.  If I choose Defrost and roll the fan switch to say Medium speed, nothing happens.  I can hear the system comeing on!  But when I click it to Hi, it comes on at high.  ANd then sometime it does not come on at all at defrost or just fan air!  Sometimes when it works, whenever I make a slight turn to the left or right the fan speed goes faster.  After I straighten the steering wheel back up, it goes back to High.  And the AC will not come on at all!  Leaving the AC on while driving on the interstate does produce very cool super slow air but the fan does not work.  How do I fix these problems?  WHere do I start?  I think I have a bad connection at the motor.  So, I got a used working fan motor at a good price. But I'm not sure what is wrong.  Any suggestions what may be the problem and where to start?  Help!

Answer
you seem to have a couple of problems although they do seem related.The intermittent fan speeds probably they fan motor as the bushings wear and the fan wobbles.Check your grounds as this too has been a problem..the body ground especially as the grounds all are attached to the body.