SOS MECHANIC CERTIFICATE -ENGINE TUNE-UP/PERFORMANCE EXAM
LATEST 2026 UPDATED QUESTIONS AND VERIFIED 100% SOLUTIONS
(2026/2027) |A+ GRADED |GUARANTEED PASS
You have examined a set of spark plugs and found white - Answers -The plug heat range is too
hot
With the vehicle operating temp and running at 2000rpm - Answers -oxygen sensor running rich
A tech is working on a car that has strong fuel odor - Answers -Stuck open canister purge valve
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
1|Page
, 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
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
2|Page
LATEST 2026 UPDATED QUESTIONS AND VERIFIED 100% SOLUTIONS
(2026/2027) |A+ GRADED |GUARANTEED PASS
You have examined a set of spark plugs and found white - Answers -The plug heat range is too
hot
With the vehicle operating temp and running at 2000rpm - Answers -oxygen sensor running rich
A tech is working on a car that has strong fuel odor - Answers -Stuck open canister purge valve
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
1|Page
, 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
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
2|Page
