Been working on the 89 IROC for the last year as time permits and have got to the point of installing the intake and engine wiring. have all the wires marks to which sensor. May have forgot one at the rear of the intake. Oil sensor on side of block. Is there a different sensor in that oil port?

 

If ur talking about the one under the distributor that is for the oil sender to the guage in the car the one at the bottom is the oil pressure cut off switch if the motor lost oil pressure it will cut the fuel pump off so u dont destroy the motor

 

The ops will would only cut power to the fp below 4psi, it will not protect your engine. It supply's power directly to the fp after the end controls the fp relay for prime.