don't know what they are, but i fixed the pic for you
on the passenger side of the fire wall there are three relay looking things. what are these things for?
TCS stands for Transmission Controlled Spark...GM started using this in 1970. That relay was riveted to the rain gutter and the wiring ran to a switch on the tranny and to a vacuum solenoid on the intake manifold. The system only allowed for full vacuum advance when the car was in high gear...this was an early smog control device.Thanks for fixing the pic.
what is the TCS?