ES300 — NEW FEATURES 18 9. Engine Control System General The VVT-i and 3-stage ACIS systems have been added to the engine control system and the EGR control has been discontinued. The engine control system of the 1MZ-FE engine in the ’99 ES300 and ’98 ES300 are compared below. * 1 : Only for California Specification Model (Continued) * 2 : For Bank 1, Sensor 2 System Outline ’99 ES300 ’98 ES300 SFI Sequential Multiport Fuel Injection An L-type SFI system directly detects the intake air mass with a hot wire type mass air flow meter. The fuel injection system is a sequential multiport fuel injection system.
ESA Electronic Spark Advance Ignition timing is determined by the ECM based on signals from various sensors. The ECM corrects ignition timing in response to engine knocking. 2 knock sensors are used to improve knock detec- tion. Torque control correction during gear shifting has been used to minimize the shift shock. IAC (Idle Air Control) A rotary solenoid type IAC valve controls the fast idle and idle speeds. VVT-i Valiable Valve Timing-intelligent Controls the intake camshaft to an optimal valve timing in accordance with the engine condition.
— ACIS Acoustic Control Induction System The intake air passages are switched according to the engine speed and throttle valve angle to in- crease performance in all speed ranges. (3-Stage) (2-Stage) Air Fuel Ratio Sensor Heater Control Maintains the temperature of the air fuel ratio sen- sor at an appropriate level to increase accuracy of detection of the oxygen concentration in the ex- haust gas. *1 Oxygen Sensor Heater Control Maintains the temperature of the oxygen sensor at an appropriate level to increase accuracy of detec- tion of the oxygen concentration in the exhaust gas.
*2 EGR Control Uses the duty control type VSV and EGR valve position sensor, controlling the EGR volume in ac- cordance with the engine condition. — Evaporative Emission Control The ECM controls the purge flow of evaporative emissions (HC) in the charcoal canister in accor- dance with engine conditions.