MICHIGAN SOS MECHANIC ENGINE TUNE-UP ACTUAL

MICHIGAN SOS MECHANIC ENGINE TUNE-UP (ACTUAL

QUESTIONS AND VERIFIED CORRECT ANSWERS

Higher voltages are required to fire signal - ----aNSWERS---- the air fuel mixture ratio is made leaner

Which of the following is true regarding fault codes - ---- aNSWERS----fault codes can be generated from past failures

A lean air fuel mixture could be - ----aNSWERS----a leaking intake manifold

Electronic fuel injection is best described by which - ---- aNSWERS----electromagnetic raises the plunges in

The oxygen sensor is reading low 02 context, what should it signal the computer - ----aNSWERS----En-rich air-fuel mixture

An EFI spays fuel into intake manifold near the intake valve - - ---aNSWERS----a port injection system

The scope pattern below was obtained 30kv - ----aNSWERS-- --29kv

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Set the ignition timing on some vehicles - ----aNSWERS---- computer controlled spark timing must be disabled

A spark plug malfunction would appear - ----aNSWERS----A

What effect would a fouled spark plug have hydrocarbon emissions - ----aNSWERS----They would increase

A tech is test driving a vehicle with a diagnose scan tool - ---- aNSWERS----intermediate tps

A car runs rough back fires through throttle body - ---- aNSWERS----faulty intake valve

Increases EGR flow at constant speeds - ----aNSWERS---- increased FI pulse width

During a compression test you get a reading of 75psi dry+80 psi wet on 4 cylinder. All other cylinders are at 140 psi. What does this mean? - ----aNSWERS----the valves are bad on cylinder 4

An exhaust gas o2 sensor - ----aNSWERS----sends signals with are recognized by the microcomputer during closed loop fail control only

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