Engine performance #7

Engine oil service is necessary due to

• increased engine/transmission vibration

• excessive heat from the combustion chamber

• the addition of emission control system

• contamination from combustion by products

Timing belt service intervals are critical on interference engines because

• over-heating might occur

• loose belts damage waterpumps

• valve damage might occur if the belt fails

• denotations might occur

Throttle-by-wire,referred to as fly-by-wire, is advantageous to a conventional throttle cable due to

• cost-effectiveness of wire as compared to cable

• improved drivability due to accurate data delivery

• lessened power output from the alternator

• eliminating hard pedal pressure caused by throttle return springs

The most efficient air/fuel mixture is

• 12.6:1

• 14.7:1

• 18.5:1

• 20.4:1

Which of the following is NOT part of a transistor?

• collector

• emitter

• grid

• base