During Warm Up

Check:

1. Idle Air Control Valve (IAC) (14)
a. Electronic Air Control Valve (EACV) (14)
b. Idle Adjusting Screw
2. Fuel Supply
a. Fuel Pressure Regulator
3. Engine Coolant Temperature (ECT) Sensor (6)
4. PGM-FI Control (ECM) Unit (BU)

NOTE: All items should be checked in the order in which they appear. A (number) after the component indicates the fault code associated with that system. If BU appears on with PGM-FI unit, it indicates the vehicle is running in back-up mode.