Howdy:

I'm working on my 1973 145. Here's a pic of a sensor I found piped in next to the alternator. I labeled the hoses so you can see that two went to the aux air valve, one went up to the intake and the unlabeled one went into that metal valve. It was spliced into my A/C lead and grounded on the intake at the cold start injector. Temp sensor #1 is in tact and wired at the air inlet. Temp sensor #2 next to thermostat in tact and factory wired. The thermo sensor is in tact and wired. Any ideas what this is and why it's spliced into the A/C?

A/c idle speed. Compressor turned on 12 volts applied to selenoid. It opens. air bypasses throttle body.speeds up idle for extra load from compressor.one lead compressor wire,other lead to ground.

That was easy, and shame on me for not thinking more logically about it. Thanks for the help. I just looked it up and it's an expensive little bugger.

It looks like an EGR valve?? May not be OE but rather an aftermarket replacement??