Intake Manifold mystery switches

[fp2112]

I am currently in the process of restoring a 1978 124 spider. Car needs to pass California smog but nearly all of the emissions stuff was disconnected (or missing) when I got the car. There are/were two switches screwed into the bottom of the intake manifold that have been cut off at the plastic connector (leaving just the brass fitting inside) and I can't seem to find any information on what those switches (or sensors) were or whether they are necessary for either a visual or tailpipe smog test. Any information would be greatly appreciated.

[BEEK]

those switches were for the emissions system, telling the temperature to relays for opening of the diverter valve solonoid, there is a circuit diagram which will provide exact function. the car should pass test without those functioning. as for visual, i wouldnt think anyone is going to look under the intake manifold to see if a switch is plugged up. because they will not know the function as well. but im not in california. i never had any problem passing georgia emissions with no smog equipment installed. they did not do a visual for years, just a tailpipe test.

[fp2112]

Thank you for the information...I really appreciate it. Does anyone know where I can find a complete emissions diagram that includes all required smog equipment for a 1978 spider? I am finding that the emissions mystery is more challenging than the valve job I just completed because of the lack of available parts and information. Thanks again!

[124JOE]

theres a couple of places to look
http://www.artigue.com
http://www.guycroft.com
these guys have alot of info posted

[WYSpider]

Does anyone know where I can find a complete emissions diagram that includes all required smog equipment for a 1978 spider?

Give these a try:
http://www.spiderroadster.com/exhaust%20System.htm
http://www.mirafiori.com/smog/smogdiag.html