My MegaSquirt wiring harness only has one idle air controller (IAC) wire, but my IAC has four or more wires.
Your vehicle's idle air controller (IAC) likely incorporates a stepper motor. This type of IAC requires a special type of driver only available in MS2, MS3, and subsequent systems. The driver is not standard hardware and must be purchased through our MegaSquirt Option Service.
If your MegaSquirt ECU is already equipped with this circuit, view our Megasquirt Option Service Connection Diagrams for a schematic of how your IAC should be connected.
If possible, you may retrofit you car with a fast idle air controller (“FIDLE”; ~1A or less) for compatibility with the standard MegaSquirt IAC circuit.
