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Hard Start

WARNING: This page is about a different car, the 2004 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.
Hard Start

Inspections Action
DEFINITION: Engine cranks OK, but does not start for a long time. Does eventually run, or may start but immediately dies.
Preliminary
  • Refer to Important Preliminary Inspections Before Starting in Symptoms - Engine Controls .
  • Inspect the engine control system grounds for being clean, tight, and in the correct locations. Refer to Power and Grounding Component Views in Wiring Systems and Engine Controls Schematics . Ensure the resistance between the engine control module (ECM) housing and the battery negative cable is less than 0.5 ohms.
  • Verify that the ECM and ECM bracket fasteners are at the correct torque.
  • Search for service bulletins that may address this condition.
Sensor/System
  • Confirm the correct operation of the theft deterrent system. Refer to Symptoms - Theft Deterrent in Theft Deterrent.
  • IMPORTANT: Allow the engine to cool before performing this test.
  • Inspect the engine coolant temperature (ECT) sensor for being skewed in value. Compare the ECT sensor value to the intake air temperature (IAT) sensor value on a cold engine. The ECT and IAT sensor values should be within +/- 3°C (5°F). If the ECT sensor is out of range with the IAT sensor, test the resistance of the ECT sensor. Refer to Temperature vs Resistance - Engine Coolant Temperature (ECT) Sensor for resistance specifications. Replace the ECT sensor if the resistance is not within the specification. Refer to Engine Coolant Temperature (ECT) Sensor Replacement . If the sensor is within the specification, repair the high resistance in the ECT signal circuit.
  • Inspect the crankshaft position (CKP) sensor for the correct resistance. The sensor resistance may be out of range after a hot soak. Measure that the resistance remains within 700-1,200 ohms at all temperatures.
Fuel System
Ignition System
  • Inspect for the correct installation of the ignition coil seals. Incorrect installation may allow water to enter the spark plug area. Inspect for moisture and corrosion.
  • Test the ignition voltage output with J 26792  Spark Tester. If you suspect an ignition system condition exists, refer to Electronic Ignition (EI) System Diagnosis .
  • Remove the spark plugs and inspect for the following conditions:
  • If the spark plugs are gas, coolant or oil fouled, determine the cause before replacing the spark plugs. Refer to the following procedures:
  • Inspect the spark plug boots and terminals for burning or micro-arcing, corrosion, and damage to the insulation.
Engine Mechanical