This oil pressure switch was used on all Vanagons from 1983-1991. Its pressure ranges are .15-.35 BAR. It is located on the engine, driver's side, between the intake push rod tubes for cylinders 3 and 4 (left side of engine looking in from the rear). This switch is NORMALLY CLOSED, and OPENS between .15 and .35 BAR, which translates to 2-5 PSI. It is the ONLY switch on 83-85 models, one of two on '86-'91 models.