This course presents engine performance troubleshooting using strategy-based diagnostics. Topics cover how to diagnose engine performance using external visual inspection, system-based strategy, diagnosis based on Diagnostic Trouble Codes (DTCs), and misfire monitoring. The course also provides information about how to diagnose engine performance support systems, including the air conditioning clutch, communications, cooling fan, cruise control, active fuel management, cam phaser, and enhanced electronic pedal override. Upon completion of this course, participants will be able to describe how to troubleshoot and diagnose engine performance concerns, and how to diagnose engine performance support systems.