11. A customer complains of blue smoke from the exhaust during startup. Which of the following is MOST likely the cause?
2727. Which tool is used to check for warpage of a cylinder head?
22. Low compression in one cylinder could be caused by:
2828. What is the purpose of the PCV system?
33. A leaking intake manifold gasket can cause:
2929. The engine cranks but will not start. There is spark and fuel pressure. What should be checked next?
44. Technician A says that detonation occurs when the air-fuel mixture ignites too early.
3030. Excessive valve lash results in:
55. What component keeps the timing chain tight?
3131. The oil pressure warning light stays on after starting the engine. The first step should be:
66. A “rod knock” noise is caused by:
3232. A faulty thermostat stuck open will cause:
77. A vacuum gauge reading fluctuates rapidly at idle. What is MOST likely the cause?
3333. A leaking intake manifold gasket on a V6 engine may cause:
88. When replacing a head gasket, which procedure is MOST important?
3434. A bent connecting rod will MOST likely cause:
99. The primary function of piston rings is to:
3535. Which of these components drives the camshaft in most overhead cam engines?
1010. Which of the following would cause oil pressure to be low?
3636. Which of the following is NOT a function of engine oil?
1111. A blown head gasket can cause:
3737. A misfire that disappears when oil is added to the cylinder indicates:
1212. Which tool is used to measure cylinder bore wear?
3838. Technician A says that detonation can be caused by low-octane fuel.
1313. When adjusting valve clearance, the engine must be:
3939. A coolant temperature sensor provides information to:
1414. A cracked cylinder head can cause:
4040. A leaking fuel injector may cause:
1515. Technician A says a compression test can identify leaking valves.
4141. A loose timing belt on an interference engine can result in:
1616. Excessive crankshaft end play can be caused by worn:
4242. The main bearings are located:
1717. An engine with low oil pressure and high oil consumption likely has:
4343. The main function of a harmonic balancer is to:
1818. Which sensor provides input to control fuel injection timing?
4444. A leaking exhaust manifold gasket can cause:
1919. If the oil appears milky, what should you suspect?
4545. The oil control ring’s main purpose is to:
2020. The camshaft turns:
4646. The crankshaft converts:
2121. Engine misfire under load can be caused by:
4747. What should always be done before reinstalling a cylinder head?
2222. A leaking valve guide seal would most likely cause:
4848. Which condition can cause an engine to “run-on” (diesel) after key off?
2323. Technician A says that aluminum blocks are lighter and dissipate heat faster than cast iron.
4949. A stuck closed PCV valve will cause:
2424. If oil pressure is high at idle but drops at highway speeds, you should suspect:
5050. Which test can identify internal coolant leaks into combustion chambers?
2525. A “sweet” smell from the exhaust usually indicates:
51✅ Answer Key (Condensed)
2626. During a cylinder leak-down test, air bubbles are seen in the radiator. This indicates:
52🧮 Scoring Guide
