CHAPTER 2

Engine Condition Diagnostics

Learning Objectives

• 2-01 Summarize the diagnostic process for engine performance issues.
• 2-02 Identify the mechanical integrity of the engine.
• 2-03 Explain how the engine creates different types of vacuum.
• 2-04 Analyze vacuum issues to diagnose engine performance issues.
• 2-05 Use scopes and scan tools to read vacuum on an engine.
• 2-06 Interpret vacuum leaks.
• 2-07 Use cylinder power balance testing to help with diagnostics.
• 2-08 Determine cylinder integrity and how it affects the operation of the engine.

ASE Education Foundation Tasks

See Appendix A to view the 2017 ASE Education Foundation Automobile Accreditation Task List Correlation Guide.

You Are the Automotive Technician

A vehicle comes into your facility with a misfire issue that cannot be accurately described to the service advisor. You must diagnose this vehicle’s misfire. Which of the following is the first step to take to fix this vehicle?

1. Replace the spark plugs.
2. Verify the customer’s concern.
3. Isolate the root cause of the issue.