GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2000 🢒 Alero Export 🢒 Engine 🢒 Engine Controls - 2.4L 🢒 Hard Start

Hard Start

Tests/Inspection

Action

DEFINITION: Engine cranks OK, but does not start for a long time. Does eventually run, or may start but immediately dies.

Preliminary
    • Confirm that the customer is using the correct starting procedure as described in the owner's manual.
    • Refer to Symptoms .
    • Search for service bulletins.

Sensor/System
    • Inspect the engine coolant temperature (ECT) sensor for being shifted in value. Connect a scan tool and compare the ECT with the intake air temperature (IAT) on a cold engine. The ECT and the IAT should be within 3°C (5°F) of each other. Test the resistance of the ECT sensor if the temperature is out of range with the IAT sensor. Refer to Temperature Versus Resistance . If the ECT sensor resistance is not within the specification, refer to DTC P0117 Engine Coolant Temperature (ECT) Sensor Circuit Low Voltage or to DTC P0118 Engine Coolant Temperature (ECT) Sensor Circuit High Voltage .
    • Test for correct operation of the manifold absolute pressure (MAP) sensor . Refer to Manifold Absolute Pressure Sensor Output Diagnosis .
    • Test for correct operation of the TP sensor.
    • Test for correct operation of the IAC valve.

Fuel System
    • Inspect for an adequate fuel level.
    • Test the fuel pump relay circuit for correct operation. Refer to Fuel Pump Electrical Circuit Diagnosis .
    • Test for incorrect fuel pressure. Refer to Fuel System Diagnosis .
    • Test for fuel contamination. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .
    • Inspect the in-tank fuel pump check valve. The in-tank fuel pump check valve may be malfunctioning, causing the fuel in the lines to drain back to the fuel tank after the engine is stopped.
        Refer to Fuel System Diagnosis .

Ignition System
    • Test for a correct ignition voltage output.
    • Inspect the spark plugs for the following conditions:
       - Any wet or fuel fouling
       - Any cracks
       - An incorrect gap
       - Any burnt electrodes or heavy deposits
    • If the spark plugs are fuel or oil fouled, the cause of the fouling must be determined before replacing the spark plugs.
    • Inspect the ignition control module (ICM) for a correct ground connection.
    • Inspect the ignition coils for cracks or carbon tracking.

Engine Mechanical

Inspect the engine for the following mechanical problems:

    • LA low compression. Refer to Engine Compression Test in Engine Mechanical.
    • A leaking cylinder head gasket. Refer to Engine Compression Test in Engine Mechanical.
    • A worn or a incorrect camshaft. Refer to Valve Train Diagnosis in Engine Mechanical.

Additional

If all of the procedures have been completed and no malfunctions have been found, test and inspect all of the connections within the suspected circuit and systems.

Observe all scan tool data for the suspected circuit and systems.