Troubleshooting

i06224976
Engine Misfires, Runs Rough
or Is Unstable
Note: If the fault is intermittent and the fault cannot
be duplicated, refer to Troubleshooting,
“Power Is
Intermittently Low or Power Cutout Is Intermittent”.
Note: If the fault only occurs under certain
conditions, test the engine under those conditions.
Examples of certain conditions are high rpm, full
load, and engine operating temperature.
Troubleshooting the symptoms under other
conditions can give misleading results.
Probable Causes
• Diagnostic codes
• Air Intake and Exhaust System
• Fuel System Inspection
• Throttle Position Sensor/Throttle Switches
• High-pressure fuel pump
• Low compression (cylinder pressure)
• Electronic unit injectors
• Individual malfunctioning cylinder
Recommended Actions
Note: The procedures have been listed in order of
probability. Complete the procedures in order.
70 UENR0612-07
Symptom Troubleshooting
This document has been printed from SPI2. NOT FOR RESALE