What is cas, crank position? I don't understand.. Is it throwing any other codes? If it's the crank position, that can definately cause a huge problem. Without that, your ignition, injection, and lots of other stuff will not work correctly... It must be working off of the remaining postion sensor. If you're OBD0 you only have the crank angle and TDC sensor I believe, but that would enough enough to at least run badly, especially if one was broken. Have you tried another distributor?