Possible Causes & Corrections

Check the following items:

• Incorrect slow idle. See appropriate SELF-DIAGNOSTICS article.
• Faulty fast idle solenoid. Replace solenoid. See appropriate SYSTEM & COMPONENT TESTING article.
• Plugged fuel return system. Remove restrictions.
• Glow plugs turn off too soon. Check glow plug system. See appropriate SYSTEM & COMPONENT TESTING article.
• Limited fuel to injection pump. Check fuel delivery system.
• Air in injection lines to nozzles. Check line fittings.
• Incorrect or contaminated fuel. Remove and replace fuel.
• Faulty injection pump. Replace pump. See appropriate REMOVAL, OVERHAUL & INSTALLATION article.
• Fuel shutoff solenoid closes in RUN position. Check solenoid operation. See appropriate SYSTEM & COMPONENT TESTING article.
• TCC stuck on. Check brake switch and PCM control.