Why does my 94 Pontiac Bonneville shifts down to 3rd gear while running long periods of time?
My 94′ Pontiac Bonneville has a mysterious transmission issue. It shifts down into 3rd gear and stays there until I reset the computer or let it sit and cool. I have changed the computer and I am still experiencing this problem. Any ideas? A: The OD is controlled through the temp. sensor. It could be defective.