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FUEL SYSTEMS TEST 1 Questions and
Correct Answers/ Latest Update / Already
Graded
Main bearing wear is being discussed. Technician A says a heavy
thumping knock at irregular intervals during acceleration may be
caused by worn main thrust bearings.
Technician B says this noise indicates loose or worn main bearings
Who is correct?
Ans: A only
Technician A says the vacuum test is one of those quick and easy tests
that can tell you a lot about the engine.
Technician B says the vacuum test measures the sealing ability of the
engine.
Who is correct?
Ans: Both A and B
A vacuum leak is suspected for a rough idle concern. Using a five-gas
infrared exhaust analyzer, Technician A says O2 will be higher than
normal.
Technician B says CO will be higher than normal.
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Who is correct?
Ans: A only
A restricted exhaust may cause any of the following except
Ans: faster than normal idle speed
Technician A says that catalytic converter operation can be confirmed
by the delta temperature test.
Technician B says that the converter operation can be confirmed by an
exhaust gas analyzer.
Who is correct?
Ans: Both A and B
Turbochargers are being discussed. Technician A says that worn shaft
seals can be indicated by bluish-white smoke in the exhaust.
Technician B says that a clogged PCV valve can cause leakage at the
shaft seals.
Who is correct?
Ans: Both A and B
A turbocharger with too little boost may be a result of
All rights reserved © 2025/ 2026 |
FUEL SYSTEMS TEST 1 Questions and
Correct Answers/ Latest Update / Already
Graded
Main bearing wear is being discussed. Technician A says a heavy
thumping knock at irregular intervals during acceleration may be
caused by worn main thrust bearings.
Technician B says this noise indicates loose or worn main bearings
Who is correct?
Ans: A only
Technician A says the vacuum test is one of those quick and easy tests
that can tell you a lot about the engine.
Technician B says the vacuum test measures the sealing ability of the
engine.
Who is correct?
Ans: Both A and B
A vacuum leak is suspected for a rough idle concern. Using a five-gas
infrared exhaust analyzer, Technician A says O2 will be higher than
normal.
Technician B says CO will be higher than normal.
All rights reserved © 2025/ 2026 |
, Page |2
Who is correct?
Ans: A only
A restricted exhaust may cause any of the following except
Ans: faster than normal idle speed
Technician A says that catalytic converter operation can be confirmed
by the delta temperature test.
Technician B says that the converter operation can be confirmed by an
exhaust gas analyzer.
Who is correct?
Ans: Both A and B
Turbochargers are being discussed. Technician A says that worn shaft
seals can be indicated by bluish-white smoke in the exhaust.
Technician B says that a clogged PCV valve can cause leakage at the
shaft seals.
Who is correct?
Ans: Both A and B
A turbocharger with too little boost may be a result of
All rights reserved © 2025/ 2026 |
