John, I had a similar problem on my 735i for the longest time and I could never figure out exactly what it was. Many people said to clean the contacts on the connector that goes to the bottom of the steering box. So, I did this and it worked kind of like yours (worked for about a day and then went back to the resistance all the time). So then what I did was take the little box off of the bottom of the steering box (be careful because all of your fluid will drain out through this hole). Then I completely disassembled it and reassembled it. Ever since then my steering has worked as it should with no problems. It's great. I still do not know how the box works but it works. Maybe you have the same problem??? I hope this might help you, Tim Bryan 88' 735i 161k