Old school survivor (sort of)...ironing out age related problems on this truck before I give it to my 16 year old. Im searching for a electrical wiring diagram as I have some relay that operates the "3 way solenoid valve" up on top of the firewall that switches vacuum to the "servo diaphragm" (#10 in diagram) that attaches to the Nikki 2bbl carburetor. It (engine speed switch) seems to ease the throttle down after you take your foot off the gas, some stupid emissions thing that unfortunately is required operational out here in Commiefornia. It seems to be controlled by an exposed relay up at the right side of the radiator. I want to replace the relay as the cover is off and it is rusting and giving me intermittant operation. When it does not work, the 3-way switch is open, vacuum is applied to "servo diaphragm" (#10) and idle is held high by this vacuum servo. Is it a generic 12V relay?

 

found an 81 wiring diagran. seems the 82 engine speed switch was moved from the cab to the front rad support under driver headlight harness. Bolted to support. My 82 FED doesnt have the yellow green coil - wire in the harness. But the Cali spec does and its a different wire orientation...weird. Be advised this schematic has the quad headlight harness, that changed in 82 to a single H/L bulb also

https://www.mazdaforum.com/forum/att..._optimized.pdf

 

I got a Haynes book. What circuit do you need?