250+ TOP MCQs on Automotive Engines and Answers

IC Engines Multiple Choice Questions on “Automotive Engines”.

1. For idling condition in automotive engines, the air-fuel mixture must be ______________
a) lean
b) rich
c) chemically balanced
d) none of the mentioned
Answer: b
Clarification: Generally, for idling condition in automotive engines, the air-fuel mixture must be a rich mixture and for cruising condition in automotive engines, the air-fuel mixture must be a lean mixture.

2. For cruising condition in automotive engines, the air-fuel mixture must be ___________
a) lean
b) rich
c) chemically balanced
d) none of the mentioned
Answer: a
Clarification: For cruising condition in automotive engines, the air-fuel mixture must be a lean mixture and for idling condition in automotive engines, the air-fuel mixture must be a rich mixture.

3. For high power condition in automotive engines, the air-fuel mixture must be ___________
a) lean
b) rich
c) chemically balanced
d) none of the mentioned
Answer: b
Clarification: For high power condition in automotive engines, the air-fuel mixture must be a rich mixture while for cruising condition in automotive engines, the air-fuel mixture must be a lean mixture and for idling condition in automotive engines, the air-fuel mixture must be a rich mixture.

4. To prevent overheating of exhaust valve and the area near it, the air-fuel mixture must be ___________
a) lean
b) rich
c) chemically balanced
d) none of the mentioned
Answer: b
Clarification: None.

5. In an automobile engine, the indication of knocking is available in the form of ___________
a) light
b) gas
c) audible sound
d) none of the mentioned
Answer: c
Clarification: Generally, in an automobile engine, indication of knocking is available in the form of audible sound.

6. The operator can make the engine operating conditions less stringent by ___________
a) jamming the throttle
b) releasing the throttle
c) engaging the throttle
d) none of the mentioned
Answer: b
Clarification: None.

7. When the throttle is suddenly opened, the mixture from the simple carburetor tends to become ___________
a) rich
b) lean
c) stoichiometric
d) not affected
Answer: b
Clarification: Generally, when the throttle is suddenly opened, the mixture from the simple carburetor tends to become lean.

8. Which of the following is a Precise petrol injection system?
a) direct injection
b) sequential injection
c) throttle body injection
d) port injection
Answer: c
Clarification: None.