Pettit Racing 185-degree Fan Switch RX7 FD3S

Our updated 185F fan switch is now easier to install, many people commented that in the original factory location, it was difficult to remove the old one and install the new one.  Also while performing the installation it was common to damage the engine temperature sensor located just above it. A damaged or broken engine temperature sensor will cause an immediate problem with fuel management preventing proper operation of the engine.


 Our updated sensor easily replaces an allen plug located on the thermostat housing just below the engine coolant cap facing the right side of the car.

Simple, easy and quick!


FYI..The factory fan switch is supposed to turn on the fans around 210F*. The old original part often doesn’t work, either from a poor connection at the switch plug or because the old plastic part finally just gave up. This is also a commonly overlooked issue on 3rd gens, which can lead to overheating.

This switch is a direct trigger for the cooling fan relays and works independent of your cars ECU, even with aftermarket computers. Works best in conjunction with the 180° RX-7 Thermostat.

*210F this higher operating temperature is used to improve emissions for US standards. Best engine longevity is achieved by maintaining cooler operating temperatures