Test yourself on your auto knowledge

Automotive Q & A

How about a checkup on your automotive knowledge? Here's a few questions based on previous column topics. The answers are at the bottom.

1. Your car requires a jump start if you park it for more than two days. What is the most likely cause? a: A worn-out battery. b: A charging system fault. c: A parasitic drain. d: Dirty battery terminals.

2. You find a small puddle of red liquid beneath your car each morning. Which of these might be the source of the leak? a: The power steering pump. b: The engine's rear main oil seal. c: The transmission pan gasket. d: The brake master cylinder.

3. Your engine loses power when accelerating hard, but runs smoothly at low speed. Which of the following is the most likely cause? a: Worn spark plugs. b: Incorrect ignition timing. c: A restricted fuel filter. d: The use of lower than specified octane fuel.

4. A burning odor is noticed, after driving a while. What may be the cause? a: A restricted radiator. b: A leaking valve cover gasket. c: A worn out battery. d: A cracked exhaust manifold.

5. Your tires are wearing smoothly, but more so in the center of the tread. What is wrong? a: An alignment fault b: Insufficient air pressure. c: Worn out struts (shock absorbers) d: Excessive air pressure

6. Your air conditioner works well while driving, but becomes marginal when stopped in traffic. Which could be the cause? a: A loose compressor drive belt. b: An inoperative condenser fan. c: A refrigerant leak. d: A loose control system vacuum hose.

7. Your check engine light begins to flash while driving. What may be wrong? a: A serious engine misfire. b: A loose gas cap. c: A minor engine control system electrical fault. d: The catalytic converter is worn out.

8. Too easy? Here's a question my students tackled recently: Student A stacks a vehicle's crankshaft and turbine shaft speed sensor waveforms on her two-channel digital storage oscilloscope. She says the frequency should be identical while driving at steady freeway speed, engine warm, with the brake pedal not applied, and then differ as the throttle is closed. Student B says an open circuit in one of the multiplex system's data bus circuits could cause the engine to start, then stall, as a result of an unsuccessful Immobilizer/PCM handshake. Which student, if any, is correct?

Answers: 1: C, 2: C, 3: C, 4: B, 5: D, 6: B, 7: A, 8: Both

Brad Bergholdt is an automotive technology instructor in San Jose. E-mail under-the-hood@earthlink.net. He cannot make personal replies.