I currently have the passenger seat of my 1992 coupe out of the car. (I'm removing the Becker radio, hence I need to do some rewiring.) Anyway, the seat back release works intermittently, i.e., it will not always release when the car is not running. Also, it will not always release when the car is running and you press the switch on the side of the seat back. The driver side seat works properly at all times. What should I check while I have the seat out? How does the vacuum system operate? I have a Mityvac if I need to apply vacuum to test it. Thanks in advance.