purchased my 1971 gs 350 conv last year. when i went to use wipers i had the following problems. put in center position runs high, put in second position just bounces up and down. after running awhile try to turn off and it won't shut off, bounces up and down. flipping switch on and off doesn't work. you have to shut the engine off and when start wipers are off. any ideas before i have to tear dash apart? checked wires on motor and they seem to match wiring specs. any help appreciated. thanks, gordon in vermont
90% of wiper problems like this are grounding issues, either at the motor, or more likely right at the switch itself. The wiper switch bolts to the backside of the plastic dash. It is not uncommon for the switch to break away from the dash. There is a ground lead on one of the attaching screws of the switch. If it isn't connected, the wipers will not shut off. Your other symptoms might be caused by the same thing. The ground lead comes off the light switch.
I had a similar problem with my '72 GS back in 2000. Solution was to connect the ground wire for the wiper switch.
Check out this thread on how to test the switch if the ground is good. Very simple... http://www.v8buick.com/showthread.php?291617-Wiper-switch-test
