what is this?

bbrroowwnn said

thanks for the diagrams......I put a new radiator in it but I still have the old one in the basement and is has no CCEGR valve on it and it is the original radiator .....

Click to expand...

The CCEGR switch is either on the radiator or the thermostat housing according to my 1980 FSM. Mine is on the housing. One port of the CCEGR switch goes to the EGR valve and the other end to the vacuum amplifier (vacuum source). So you could follow all the lines from the vacuum amplifier and see where they go. If your 72 is anything like that of course. :D