Hard Start

WARNING: This page is about a different variant/trim than selected.

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 module (ECM) grounds for being clean, tight, and in the proper locations. Refer to Power and Grounding Component Views in Wiring Systems and Engine Controls Schematics . Search for service bulletins that may address this condition.
Sensor/System	Confirm the correct operation of the theft deterrent system. Refer to Diagnostic System Check - 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. Connect a scan tool. Compare the ECT against the intake air temperature (IAT) on a cold engine. The ECT and IAT sensor values should be within +/- 3°C (5°F) of each other. 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 MAF sensor installation. A MAF sensor that is incorrectly installed may cause a hard start. Refer to Mass Air Flow (MAF)/Intake Air Temperature (IAT) Sensor Replacement . Verify proper operation of the throttle actuator control (TAC) system by performing the following procedure: Observe the TP sensor angle with a scan tool Turn the key ON, with the engine OFF. Slowly depress the accelerator pedal to wide open throttle (WOT), then slowly return the pedal to the rest position. Repeat several times. TP sensor angle should increase to near 100 percent as the pedal is depressed, and decrease as the pedal is released. A verification of the entire TAC system will be performed.
Fuel System	Test the fuel pump relay operation. Refer to Fuel Pump Electrical Circuit Diagnosis . Test for any of the following fuel pressure related conditions. Refer to Fuel System Diagnosis . An inoperative check valve in the fuel pump allowing the fuel in the lines to drain back to the tank after the engine stops Incorrect fuel pressure Restricted fuel filter Test for a contaminated fuel condition. Refer to Alcohol/Contaminants-in-Fuel Diagnosis (w/o Special Tool) or Alcohol/Contaminants-in-Fuel Diagnosis (w/ Special Tool) . Test for plugged or restricted injectors. Refer to Fuel Injector Balance Test with Special Tool .
Ignition System	Test for proper ignition system operation. Refer to Electronic Ignition (EI) System Diagnosis . Remove the spark plugs and inspect for the following conditions. Refer to Spark Plug Replacement . Correct heat range Wet plugs Cracks Wear Improper gap Burned electrodes Heavy deposits Determine the cause of the fouling before replacing the spark plugs if the spark plugs are gas, coolant or oil fouled. Refer to Spark Plug Inspection . Once you determine the cause of the fouling, refer to one of the following procedures: For diagnosis of a rich condition, refer to DTC P0172 or P0175 . For diagnosis of coolant contaminated spark plugs, refer to Loss of Coolant (M 35) or Loss of Coolant (M 82) in Engine Cooling. For diagnosis of oil fouled spark plugs, refer to Oil Consumption Diagnosis in Engine Mechanical.
Engine Mechanical	Low cylinder compression-Refer to Engine Compression Test in Engine Mechanical. Combustion chambers for excessive carbon buildup-Clean the chambers using top engine cleaner. Follow the instructions on the can. Inspect for incorrect camshaft timing-Refer to Timing Belt Timing Procedure in Engine Mechanical. Excessive oil in combustion chamber due to leaking valve seals-Refer to Oil Consumption Diagnosis in Engine Mechanical. Inspect the following components for incorrect basic engine parts: The cylinder heads-Refer to Cylinder Head Cleaning and Inspection in Engine Mechanical. The camshafts-Refer to Camshaft and Bearings Cleaning and Inspection in Engine Mechanical. The pistons, connecting rod, and/or bearings-Refer to Piston, Connecting Rod, and Bearings Cleaning and Inspection in Engine Mechanical.