my oil pressure is not reading and i dont know which sensor to check.

also my tranny (auto) has problems locking in to gear and is shifting late. I jacked the car up and there is a big stain on the floor at about the middle of my racing pipe.. could that mean my rear main seal is broke and how could i do a quick fix....?

 

Can't believe no body answered you. The oil pressure sensor is below the oil filter. Screwed in the side of the housing. About 21/2 inches round. The single wire connector is mounted on the outside end of the sensor. It slides on. Wire gets knocked off sometimes. Never owned an automatic car.Can't help there.