Because of the adaptive capability of the Digifant I control unit, it must be reset to its reference setting after certain conditions or repairs. They are:
The blue coolant temperature sensor connector has been disconnected with the engine running
The following components have been replaced:
Digifant control unit
air flow sensor
throttle valve potentiometer
throttle valve body
When resetting the control unit, the engine must be at normal operating temperature, all electrical accessories must be Off, the idle stabilization system must be OK, and the exhaust system must be leak-free.
Coolant temperature sensor connector (arrow) on 1989 and later Digifant II system (engine codes RV and PF) disconnected for test.
Crankcase ventilation hose disconnected from emission control valve (arrow) and plugged for idle mixture (% CO) adjustment.
To reset Digifant I control unit:
With the engine off, disconnect the crankcase ventilation hose from the emission control valve atop the valve cover, then plug the hose. See earlier Fig. 7-19.
Start the engine and let it idle.
Disconnect the blue coolant-temperature sensor harness connector. See earlier Fig. 7-18.
Let the engine idle for 1 minute, then reconnect the harness connector.
Do not reconnect the coolant temperature sensor harness connector while the radiator cooling fan is running.
Turn the engine off and reconnect the crankcase ventilation hose.