Puzzler, incorrect camshaft installation

One of the recent podcasts had an interesting puzzler, a mechanic installed the wrong version of the camshaft for the engine. The symptoms were low oil pressure and idle rpm racing. Ray explained why this could cause low oil pressure, but not so much about the idle rpm racing. Apparently the mechanic who made the mistake solved their customer’s complaint about the oil light illumination by disconnecting the light … well, that’s an ingenious solution!!! … lol … Anyway Ray implied that the cause of the idle racing had something to do with disconnecting the oil light. Any idea why this would be? I believe this vehicle was a MOPAR product (2.2 L engine as I recall) from the 1980’s & used an electric-modulated carburetor. Why would disconnecting a dashboard warning light cause an increase in idle rpm?

Installing the correct camshaft was the solution to the low oil pressure. Reconnecting the oil warning light solved the idle racing.

The oil pressure switch had a 3-pin connector, one for the warning light and the other two were an off/on switch to power the electric choke heater. With the coke heater disabled, the choke doesn’t open and the carburetor stays on fast idle.

Ok, so disconnecting the connector disconnects more than one thing. I was thinking it was disconnected right at the bulb. Thanks, confusion solved!