Hello everyone. This is my first post. I'm interested in a 944 (year unsure, but 1st gen w/ square dash, so somewhere from '82-'85) that has bad reference sensor(s). The car is very affordable, but in all-around rough shape.Seller says it will run with the new sensor. Can these be replaced with the motor andtransstill in the car? How do I know which one is bad? I've heard they get filthy, so I was wondering if a thorough cleanining can sometimes substitute replacement? Also, what other problems should I be wary of? The seller says even now it will run on a "warm, dry day," so I think most of the car's problems are cosmetic. Thanks a lot for any advice.