ENGINE UNIT


  1. OUTLINE


    1. The A25A-FKS engine is an in-line 4-cylinder, 2.5 liter, 16 valve DOHC engine.

    2. The engine adopts the Dual Variable Valve Timing-intelligent (Dual VVT-i) system which realizes optimal valve timing by using electric motors to actuate the intake camshaft actuators and engine oil pressure to actuate the exhaust camshaft actuators. In addition, this engine uses a high-expansion ratio Atkinson cycle, Direct injection 4-stroke gasoline engine Superior version (D-4S) system, Direct Ignition System (DIS), Electronic Throttle Control System-intelligent (ETCS-i) and Exhaust Gas Recirculation (EGR) system employing a highly efficient EGR cooler. Thus, improved engine performance, quietness, fuel economy and cleaner emissions have been achieved.

  2. SPECIFICATION

    Engine Type A25A-FKS
    No. of Cyls. & Arrangement 4-cylinder, In-line
    Valve Mechanism

    16-valve DOHC, Chain Drive

    (With VVT-iE and VVT-i)
    Combustion Chamber Pentroof Type
    Flow of Intake and Exhaust Gasses Cross-flow
    Fuel System Sequential Multiport Fuel Injection (SFI) D-4S
    Ignition System Direct Ignition System (DIS)
    Displacement

    cm3(cu. in.)

    		 2487 (151.8)
    Bore x Stroke mm (in.) 87.5 x 103.4 (3.44 x 4.07)
    Compression Ratio 13.0 : 1
    Max. Output (EEC) kW@rpm 152@6600
    Max. Torque (EEC) N*m@rpm 243@5000
    Valve Timing Intake Open -30° to 40° BTDC
    Closed 110° to 40° ABDC
    Exhaust Open 19° to 60° BBDC
    Closed 41° to 0° ATDC
    Spark Plug Type DENSO Made FC16HR-Q8
    Plug Gap mm (in.) 0.7 to 0.8 (0.0276 to 0.0315)
    Firing Order 1 - 3 - 4 - 2
    Octane Rating 87 or higher
    Research Octane Number 91 or higher
    Emission Regulation LEVIII-ULEV50
    Engine Service Mass* (Reference) kg (lb) 121.6 (268)

    *: The figure shown is the weight of the part without coolant and oil.

    Figure 1. Performance Curve

    B006WM1E01

  3. MAIN FEATURES


    1. The A25A-FKS engine has achieved the following through the use of the items listed in the table below.


      1. High performance and reliability

      2. Low noise and vibration

      3. Lightweight and compact design

      4. Good serviceability

      5. Clean emissions and improved fuel economy

        Item i ii iii iv v
        The high-expansion ratio Atkinson cycle is adopted. ○ - - - ○
        Engine Proper An aluminum cylinder block sub-assembly is used. - - ○ - -
        Spiny-type liners are used in the cylinder bores. ○ - - - -
        A cylinder block water jacket spacer is used. ○ - - - ○
        The piston skirt is coated with resin. ○ ○ - - ○
        An offset crankshaft is used. ○ ○ - - ○
        Laser cladded valve seats are used for the intake side. ○ - - - ○
        A resin gear engine balancer assembly is used. - ○ ○ - -
        A chain cover that consists of the timing chain cover assembly and No. 2 timing gear cover assembly is used. ○ - - - -
        Bolts with smaller heads than standard bolts of the same thread diameter are used. ○ - ○ - -
        Valve Mechanism The Variable Valve Timing-intelligent by Electric motor (VVT-iE) system is used for the intake camshafts. ○ - - - ○
        The Variable Valve Timing-intelligent (VVT-i) system is used for the exhaust camshafts. ○ - - - ○
        A chain sub-assembly and No. 1 chain tensioner assembly are used. - ○ - ○ -
        Valve lash adjuster assemblies are used. ○ ○ - ○ -
        No. 1 valve rocker arm sub-assemblies are used. ○ - - - ○
        Lubrication System A cartridge type oil filter sub-assembly is used. - - - ○ -
        An electronically controlled variable displacement oil pump is used. ○ - - - ○
        An engine oil level sensor is used. - - - - ○
        Cooling System TOYOTA Genuine Super Long Life Coolant (SLLC) is used. - - - ○ -
        A variable passage cooling system is used. ○ - - - ○
        An electric engine water pump assembly is used. - - - - ○
        Intake and Exhaust System An intake manifold made of plastic is used. - ○ ○ - -
        A linkless type throttle body with motor assembly is used. - - ○ ○ -
        A stainless steel exhaust manifold assembly is used. - - ○ - -
        Emission Control System A step motor type Exhaust Gas Recirculation (EGR) valve is used. ○ - - - ○
        A water-cooled type Exhaust Gas Recirculation (EGR) cooler is used. ○ - - - ○
        An ultra thin-wall, high-cell density ceramic type Three-Way Catalytic converter (TWC) is used. - - - - ○
        Fuel System A Direct injection 4-stroke gasoline engine Superior version (D-4S) system is used. ○ - - - ○
        A fuel returnless system is used. - - ○ ○ ○
        Quick connectors are used to connect the fuel hoses with the fuel pipes. - - - ○ -
        10-hole type low pressure port fuel injector assemblies are used. ○ - - - ○
        6-hole type high pressure direct fuel injector assemblies are used. ○ ○ - - ○
        Ignition System The Direct Ignition System (DIS) is used. ○ - - ○ ○
        Long-reach type iridium-tipped spark plugs are used. ○ - - ○ ○
        Serpentine Belt Drive System A serpentine belt drive system is used. - - ○ ○ -
        Engine Control System Magnetic Resistance Element (MRE) type camshaft position sensors and crank position sensor are used. ○ - - - ○
        The Electronic Throttle Control System-intelligent (ETCS-i) is used. ○ - - - ○
        The cranking hold function is used. ○ - - - -
        An evaporative emission control system is used. - - - - ○

        ○: Applicable

        -: Not applicable

    2. Location of small-head bolts

      B006WCS
      B006WJL
      B006WQB