[65comet]

The stalk switch portion that is inside the steering column has probably had the contacts over heat and melted the surrounding plastic. This has probably moved the contacts position so that they come on when they shouldn't and don't come on when they should. I have taken one apart in the past and cleaned the plastic off the contacts and used a soldering iron to melt the plastic to get the contacts back into the correct position but I don't recommend it as it doesn't last very long. Only something for the situation where you can't get a new one any more because the car is old. I suggest getting a new one.