2.6L Feedback Carburetor Testing: Description: Notes

NOTE: Information on this system is also covered in the FUEL SYSTEMS section. Additional diagnostic information that relates strictly to the fuel portion of this system can be found in the MIKUNI 2-BBL - 2.6L article in the FUEL SYSTEMS section.

The computerized engine control system is used on California and Federal 2.6L engines equipped with Mikuni 2-barrel carburetors. The carburetor has 3 air/fuel solenoids and a throttle opener to control air/fuel mixture for all operating conditions. The electronic control unit (ECU) monitors several sensors and switches on the engine to adjust fuel flow to maintain a 14:1 air/fuel ratio.

When certain operating conditions are met, the ECU goes into closed loop mode. The ECU monitors throttle position (except idle), idle position, engine speed, coolant temperature, intake air temperature and exhaust oxygen content. The ECU uses this information to control carburetor solenoid duty cycle, throttle opener, deceleration spark control and air conditioner control.