Many states require the back-up lights to work in order to pass inspections. The 850/S/V/70 automatic transmission uses the PNP switch to make the electrical connections needed for the back-up lights to work, the Manual transmission uses a switch on top of the transmission to complete the circuit. If you have a manual transmission and the only way you can get the light to come on and stay on is to pull back on the shifter or jiggle it, then you more than likely need a new reverse light switch. The switch is located just underneath the inboard section of your air box. If you have an automatic transmission, look to the PNP switch replacement post.

         Start by removing items, #1 is the air intake tube. #2 is the pre-heater hose, #3 is the intake to the throttle body, the clamp on the air box is 7mm and you can get by with just taking off the section attached to the air box. #4 is the connection for the Mass Air Flow meter, #5 is a control valve that has an electrical connection in the front and two vacuum lines, one on the bottom and one in the back. #6 is the coil wire to the distributor. Once everything is disconnected and out of the way, pull up on the inboard section of the air box and it will come un-clipped from the fastners, then push the box in to slide out a guide that goes into the fender. Working the box out requires a little bit of patients. Once the box is out you should have the below view.

         The electrical connector just pulls off the switch. An oxygen sensor socket or a 7/8 will fit the connector. Just unscrew it and replace it with the new one. Just to the right of the switch you can get a good look at what the air box snaps into to keep it in place.