Chapter 53 PowerPoint

Define these Technical Terms using the textbook:

1. engine load

2. hesitation

3. misfiring

4. noid light

5. rough idle

6. stall

7. stumbling

8. surging

9. troubleshooting chart

10. vacuum gauge

Answer these discussion questions using the textbook:

1. List the most common engine performance problems.

Read the chapter summary below:

■ An engine performance problem is any trouble that affects the power, fuel economy, emission output levels, and dependability of the engine.

■ A systematic approach to troubleshooting, also termed strategy-based diagnostics, involves using your knowledge of automotive service and a logical process of elimination to find the source of a problem.

■ Problem symptoms are the noticeable changes in performance to the system or part: abnormal noise, loss of power, rough idle, hesitation, etc.

■ Engine misfiring is a performance problem resulting from one or more cylinders failing to fire.

■ A vacuum leak is a common cause of rough idling. If a vacuum hose hardens and cracks, it will allow outside air to enter the intake manifold, bypassing the throttle body.

■ A hesitation is a condition in which the engine does not accelerate normally when the gas pedal is pressed.

■ Stumbling is similar to a hesitation, but the engine misses instead of temporarily losing power and jerking upon acceleration.

■ Surging is a condition in which engine power fluctuates up and down with a continuous, soft jerking motion.