Engine Control System (4HK1) 1A-347
Hard Start
Checks Action
Definition:
The engine cranks OK, but does not start for a long time. The engine does eventually run, or may start but
immediately dies.
Preliminary Checks • Diagnostic System Check - Engine Controls.
• Ensure the driver is using the correct starting procedure.
• Inspect the ECM grounds for being clean, tight, and in their proper
locations.
• Inspect that the harness connectors are correctly connected.
• Inspect the fuel type and quality.
• Inspect the programmed fuel injector ID code for each cylinder.
• Inspect the Scan Tool Data List in this section.
• Inspect the Service Bulletin.
Sensor Checks Inspect the engine control sensors for the following conditions. Refer to the
Scan Tool Data List in this section.
• Compare the Coolant Temperature with the Intake Air Temperature (IAT)
and Fuel Temperature (FT) parameters on a cold engine condition. If the
difference among temperature reading is more than 5°C (9°F) on a cold
engine, check for high resistance in each circuit or for a skewed sensor.
Notice: The mass air flow (MAF) sensor is heated and as a result the IAT may
indicate a higher than normal intake air temperature if the ignition switch is
being ON.
• Observe the Fuel Rail Pressure (FRP) Sensor parameter with the engine
OFF. The FRP Sensor should read 0.9 to 1.0 volt with the ignition switch
ON and engine OFF after the engine has stopped running for a minimum of
1 minute. If not, check for high resistance in each circuit or for a skewed
sensor.
• Crankshaft position (CKP) sensor is tight and the sensor rotor is not
damaged.
• Camshaft position (CMP) sensor is tight and the camshaft gear is not
damaged.
LG4HKED-WE-0871.book 347 ページ ２００７年１１月２９日 木曜日 午後６時２９分
To Next Page
Loading...
Need help?
General
