Turn Signal Problems

[geloso]

I have an 85.5 944 and have noticed over the past year that when I put my turn signal on to turn left and complete the turn it doesn't automatically return to the center position. Sometimes when the weather is colder it acts normally. On making right turns, it functions normally regardless of the weather or anything else. I've been thinking about replacing the turn signal indicator assembly, but was wondering if it may be something else like a portion of the steering wheel assembly. Can anyone give me a good place to start without tearing the whole steering column down needlessly?