it was located on the lower pass side of the block, between cylinders 4 and 6. im thinking its a knock sensor, but ive seen something very similar on a carbed 350 so now im not sure. wire was a single plug, i believe brown. the car is an 86 tpi.

 

With one wire it should be an oil pressure sensor.

 

That is your knock sensor.

 

if its between the cylinders up high on the head its the switch for your fan. if its down low closer to the pan and on the block its the knock senser. both look simalar and are on the passager side and use the same type of connector.

the oil pressure senser is on the DRIVER side so disregard what JR said. he didnt read correctly. sorry JR.....

 

alrighty, thanks for the clarification. i wasnt able to get it off my old block before i scrapped it so i have to buy a new one. im just glad i labeled all my connectors before i tore my car apart.