GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2002 🢒 Safari - 2WD 🢒 Engine 🢒 Engine Electrical 🢒 Hard Start

Inspections

Action

DEFINITION: The engine cranks normally, but does not start in a normal amount of time. The engine does eventually run, or may start but immediately dies.

Preliminary Inspections
    • Refer to Symptoms - Engine Controls .
    • Ensure that the vehicle operator is using the correct starting procedure.

Sensor
    • Observe the engine coolant temperature (ECT) sensor parameter with the scan tool. Compare the engine coolant temperature with the ambient air temperature on a cold engine. If the coolant temperature reading is more than 5 degrees more or less than the ambient air temperature on a cold engine, inspect for a high resistance or low resistance in the coolant sensor circuit.
    • Inspect the throttle position (TP) sensor. If a sticking throttle shaft or binding linkage causes a high TP sensor voltage, or an open throttle indication, the control module will not control the idle. While monitoring the TP sensor voltage parameter, the scan tool should display less than 0.9 volt with the throttle closed.

Fuel System

       Important: A damaged in-tank fuel pump check valve will allow the fuel in the lines to drain back to the tank after the engine stops.

    • Inspect the fuel pump relay for proper operation. The fuel pump should operate for the first 2 seconds when turning ON the ignition. Refer to Fuel Pump Electrical Circuit Diagnosis .
    • Inspect the fuel pressure. Refer to Fuel System Diagnosis .
    • Inspect for water contamination in the fuel. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .
    • Perform the fuel injector coil test. Refer to Fuel Injector Solenoid Coil Test .
    • Perform the fuel injector balance test. Refer to Fuel Injector Balance Test with Tech 2 .
    • Inspect the fuel pump check valve. Refer to Fuel System Diagnosis .

Ignition System
    • Test for the proper ignition voltage output with J 26792 spark tester or the equivalent.
    • Inspect the spark plugs. Refer to Spark Plug Inspection .
    • Inspect for bare or shorted spark plug wires. Refer to Spark Plug Wire Inspection .
    • Inspect for moisture in the distributor cap.
    • Inspect for loose ignition coil connections.
    • Inspect for loose ignition control module connections.
    • Inspect for a faulty ground at the control module or within the ignition system.
    • Inspect the ignition control (IC) circuit for an open or short to ground. Refer to Testing for Continuity , or Testing for Short to Ground in Wiring Systems.

Engine Mechanical
    • Inspect for the following:
       - Improper valve timing
       - Low compression--Refer to Engine Compression Test in Engine Mechanical.
       - Bent pushrods--Refer to Valve Rocker Arm and Push Rod Cleaning and Inspection in Unit Repair.
       - Worn rocker arms--Refer to Valve Rocker Arm and Push Rod Cleaning and Inspection in Unit Repair.
       - Broken or weak valve springs
       - Worn camshaft lobes -- Refer to Camshaft and Bearings Cleaning and Inspection in Unit Repair.
    • Inspect the intake and exhaust manifolds for casting flash. Refer to Intake Manifold Cleaning and Inspection in Engine Mechanical.

Additional
    • Inspect the idle air control (IAC) operation. Refer to Idle Air Control (IAC) System Diagnosis .
    • Inspect for a restricted exhaust. Refer to Restricted Exhaust in Engine Exhaust.