I don't know if this will help. I had a 85 Lynx had wierd things like your describing going on. I had to go to the dealer and have them find the problem. It turned out to be a loose grounding screw in of all places it was on the passenger side kick board, evidently someone at the factory forgot to remove a paper washer causing a poor conection.It took about 3 years to show up. I felt it was above my realm knowledge. ELECTRICAL
what a pain. Fixed for the 1 hour mininum charge.