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ray_mcavoy · 01-26-2023, 07:48 PM

I believe that's off a newer engine ... probably mid/late 70's or 80's ... not original for 67-72.

Those thermal vacuum switches (TVS) were used to control a variety of things ... like EGR valves and other emissions equipment.

01-26-2023, 07:48 PM	#2
ray_mcavoy Registered User Join Date: Nov 2009 Location: Sherman, ME Posts: 2,355	Re: Thermostat Housing Switch I believe that's off a newer engine ... probably mid/late 70's or 80's ... not original for 67-72. Those thermal vacuum switches (TVS) were used to control a variety of things ... like EGR valves and other emissions equipment.