Data Senders

The following data senders are used in addition to the oxygen sensor to provide the microprocessor with engine operating data.



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The system on these engines uses two vacuum operated electric switches, one mechanically operated electric switch, one engine coolant operated switch (dual function) and one air temperature operated electric switch to detect and send engine operating data to the MCU. These senders detect cold engine start-up and operation, wide open throttle, idle (closed throttle) and part and deep throttle.
The thermal electric switch is located within the air cleaner and provides either a ground circuit for the microprocessor to indicate the need for a cold weather engine start-up (when air temperature is below the calibration point) or an open circuit to indicate normal engine start up (when air temperature is above the calibrated temperature).
The coolant temperature switch is a dual function unit that is controlled by engine coolant temperature and is integral with the intake manifold (EFE) heater control switch. When closed, the switch indicates that the engine is cold (coolant temperature below 135° F).
The 4 inch Hg vacuum switch is controlled by carburetor ported vacuum and has a normally closed electrical contact that indicates a closed throttle condition. The switch is opened by a 4 inch Hg vacuum level.
The 10 inch Hg vacuum switch is controlled by manifold vacuum. When open, the switch indicates a deep throttle condition (therefore, non-cruise engine operating condition.
The wide open throttle (WOT) switch is a mechanically operated electrical switch that is located at the base of the carburetor and is controlled by throttle position to indicate a wide open throttle condition. In order for this system to operate properly, all associated components and related systems must be intact and operational. This includes the EGR valve and related components, correct ignition advance vacuum hose routing, etc.