greg454

I know my water temp sender is in my left cyl head but what is the one in the right cyl head for? It looks like maybe a switch. it has two terminals which are jumped together and then one wire which goes into the wiring harness. It looks like factory wiring. I dont have a electric fan. Any thoughts?

Joe Lucia

greg-----


Yes, the unit that you described which is mounted in the right side cylinder head and which has the 2 spade connectors is a temperature switch for the transmission controlled spark (TCS) system. This unit works in conjunction with other elements of the TCS system, including a transmission mounted switch, a firewall mounted relay, and an intake manifold mounted solenoid to interrupt vacuum signal to the distributor vacuum advance control during certain engine operating parameters in order to reduce exhaust emissions.

Most of these systems were disabled/removed by previous owners of the cars. However, it is emissions-illegal to do so and states which have emissions inspections will likely fail a car for this alteration.

greg454

Thanks joe, I had no clue what that thing was. Im assuming that since the two terminals are jumpered together that it is disabled.

73 LS-4

Thanks, now I know what that was for, I was wondering about that while I was installing the headers since mine wasn't hooked up either.

Pat Kunz