Edmunds Answers

Voted Best Answer

  • avatar MrShift@Edmunds 01/18/13 12:09 pm PST

    You might check the following:


    1. DESCRIPTION
    The fuel pressure regulator (1) is a diaphragm-operated cartridge relief valve with the fuel pump pressure on one side and the regulator spring pressure and intake manifold vacuum on the other. A retainer (2) holds the fuel pressure regulator.

    PURPOSE
    The regulator's function is to maintain a constant pressure differential across the injectors at all times. The pressure regulator compensates for engine load by increasing the fuel pressure as engine vacuum drops.

    OPERATION
    With the ignition ON leaving the engine off (zero vacuum), the fuel pressure at the pressure test connection should be 415-455 kPa (6O-66 psi) . If the pressure is too low, poor performance could result. If the pressure is too high, excessive odor may result.

    2.


    DESCRIPTION
    The engine coolant temperature sensor is a thermistor (a resistor which changes value based on temperature) mounted in the engine coolant passage. Low coolant temperature produces a high resistance 100,000 ohms at -40°C (-40°F) while high temperature causes low resistance 70 ohms at 130°C (266°F).

    OPERATION
    The VCM supplies a 5 volt signal to the engine coolant temperature sensor through a resistor in the VCM and measures the voltage. The voltage will be high when the engine is cold. The voltage will be low when the engine is hot. By measuring the voltage, the VCM calculates the engine coolant temperature. Engine coolant temperature affects most systems the VCM controls.

    The scan tool displays engine coolant temperature in degrees. After engine start-up, the temperature should rise steadily to about 9O°C (194°F) then stabilize when thermostat opens. If the engine has not been run for several hours (overnight), the engine coolant temperature and intake air temperature displays should be close to each other. When the VCM detects a malfunction in the Engine Coolant Temperature (ECT) sensor circuit, the following Diagnostic Trouble Code (DTC) s will set:

    DTC P0117 circuit low.
    DTC P0118 circuit high.
    DTC P0125 excessive time to Closed Loop.
    DTC P1114 circuit intermittent low.
    DTC P1115 circuit intermittent high.

Answers

  • MrShift@Edmunds 01/18/13 12:09 pm PST

    You might check the following:


    1. DESCRIPTION
    The fuel pressure regulator (1) is a diaphragm-operated cartridge relief valve with the fuel pump pressure on one side and the regulator spring pressure and intake manifold vacuum on the other. A retainer (2) holds the fuel pressure regulator.

    PURPOSE
    The regulator's function is to maintain a constant pressure differential across the injectors at all times. The pressure regulator compensates for engine load by increasing the fuel pressure as engine vacuum drops.

    OPERATION
    With the ignition ON leaving the engine off (zero vacuum), the fuel pressure at the pressure test connection should be 415-455 kPa (6O-66 psi) . If the pressure is too low, poor performance could result. If the pressure is too high, excessive odor may result.

    2.


    DESCRIPTION
    The engine coolant temperature sensor is a thermistor (a resistor which changes value based on temperature) mounted in the engine coolant passage. Low coolant temperature produces a high resistance 100,000 ohms at -40°C (-40°F) while high temperature causes low resistance 70 ohms at 130°C (266°F).

    OPERATION
    The VCM supplies a 5 volt signal to the engine coolant temperature sensor through a resistor in the VCM and measures the voltage. The voltage will be high when the engine is cold. The voltage will be low when the engine is hot. By measuring the voltage, the VCM calculates the engine coolant temperature. Engine coolant temperature affects most systems the VCM controls.

    The scan tool displays engine coolant temperature in degrees. After engine start-up, the temperature should rise steadily to about 9O°C (194°F) then stabilize when thermostat opens. If the engine has not been run for several hours (overnight), the engine coolant temperature and intake air temperature displays should be close to each other. When the VCM detects a malfunction in the Engine Coolant Temperature (ECT) sensor circuit, the following Diagnostic Trouble Code (DTC) s will set:

    DTC P0117 circuit low.
    DTC P0118 circuit high.
    DTC P0125 excessive time to Closed Loop.
    DTC P1114 circuit intermittent low.
    DTC P1115 circuit intermittent high.

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