ASE A1 (Engine Repair) Practice Test –
Cumulative Questions And Answers Plus
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Terms in this set (185)
an engine miss is being diagnosed A only:
using a cylinder leakage test.
Technician A says that any cylinder If cylinder leakage exceeds 20%, check for air
with over 20% leakage has escaping the tailpipe, the PCV valve opening in
excessive leakage. Tech B says that the rocker arm cover, and the top of the throttle
air leaking from the tailpipe body or carburetor.
indicates a cracked cylinder.
Air leaking from the tailpipe usually indicates an
A only, exhaust valve leak
B only,
A & B,
Neither .
,during a compression test, a worn piston rings
cylinder has 40% of the specified
compression reading. When the if compression increases during a wet test, this
tech performs a wet test, the indicates worn piston rings. Compression would
compression reading on this not increase if an exhaust valve is burned, intake
cylinder has 75% of the specified valve is bent, or camshaft lobe is worn.
reading. The cause of the low
compression reading could be
worn piston rings,
a burned exhaust valve,
a bent intake valve,
a worn camshaft lobe,
the customer complains that the valve train operation:
engine cranks but does not start;
the first thing to check should be if the engine cranks properly, the battery is not
the problem. Compression would not be the
valve train operation, FIRST test, and because engine vacuum is low
battery voltage, during a crank, a vacuum test would not be
compression, conclusive.
engine vacuum,
,during a cylinder balance test on an Both A&B
engine with fuel injection, one
cylinder provides very little rpm Both a misfiring ignition system and an intake
drop. manifold leak could cause a cylinder to
Tech A says the ignition system may contribute too little power
be misfiring on that cylinder.
Tech B says the engine may have an
intake manifold vacuum leak.
A only,
B only,
A & B,
Neither ,
while discussing basic diagnostic B
procedures,
Tech A says the most complicated Always attempt the more simple diagnosis first
diagnostic tests should be
performed first. Tech B says that
you should first question the
customer to obtain as much info as
possible about the problem
A,
B,
A & B,
Neither,
with the engine idling, a vacuum sticky valve stems and guides
gauge connected to the intake
manifold fluctuates (from 15 to 20).
These fluctuations may be caused -late ignition timing would result in a low, steady
by reading
-intake manifold leaks would cause a very low,
late ignition timing, steady reading
intake manifold vacuum leaks, -a restricted exhaust system would cause vacuum
a restricted exhaust system, to slowly decrease after the engine was
sticky valve stems and guides, accelerated and held steady
, oil is leaking from the crankshaft A&B
rear main bearing seal on an
engine. Tech A says the oil seal
could be faulty. Tech B says the
PCV system may not be
functioning.
A,
B,
A & B,
Neither,
A high-pitched squealing noise is small leak in exhaust manifold
heard during hard acceleration. This
may be the cause of: -intake manifold leak causes a high-pitched
whistle at idle and low speeds
intake manifold leak, -carb choke stuck closed will not cause a high-
the choke stuck closed pitched whistle
fuel system leak -fuel system leak normally would not cause a
small leak in exhaust manifold noise
a heavy thumping noise occurs with loose flywheel bolts
the engine idling, but the oil
pressure is normal. this may be -worn pistons and cylinders would cause a
caused by: thumping noise during acceleration
-worn main bearings cause a thump when the
worn pistons and cylinders, engine is started
loose flywheel bolts, -loose camshaft bearings would cause a
worm main bearings, growling noise at all times
loose camshaft bearings,
Cumulative Questions And Answers Plus
Rationale With Complete Solution | 2026/27
Update
Save
Terms in this set (185)
an engine miss is being diagnosed A only:
using a cylinder leakage test.
Technician A says that any cylinder If cylinder leakage exceeds 20%, check for air
with over 20% leakage has escaping the tailpipe, the PCV valve opening in
excessive leakage. Tech B says that the rocker arm cover, and the top of the throttle
air leaking from the tailpipe body or carburetor.
indicates a cracked cylinder.
Air leaking from the tailpipe usually indicates an
A only, exhaust valve leak
B only,
A & B,
Neither .
,during a compression test, a worn piston rings
cylinder has 40% of the specified
compression reading. When the if compression increases during a wet test, this
tech performs a wet test, the indicates worn piston rings. Compression would
compression reading on this not increase if an exhaust valve is burned, intake
cylinder has 75% of the specified valve is bent, or camshaft lobe is worn.
reading. The cause of the low
compression reading could be
worn piston rings,
a burned exhaust valve,
a bent intake valve,
a worn camshaft lobe,
the customer complains that the valve train operation:
engine cranks but does not start;
the first thing to check should be if the engine cranks properly, the battery is not
the problem. Compression would not be the
valve train operation, FIRST test, and because engine vacuum is low
battery voltage, during a crank, a vacuum test would not be
compression, conclusive.
engine vacuum,
,during a cylinder balance test on an Both A&B
engine with fuel injection, one
cylinder provides very little rpm Both a misfiring ignition system and an intake
drop. manifold leak could cause a cylinder to
Tech A says the ignition system may contribute too little power
be misfiring on that cylinder.
Tech B says the engine may have an
intake manifold vacuum leak.
A only,
B only,
A & B,
Neither ,
while discussing basic diagnostic B
procedures,
Tech A says the most complicated Always attempt the more simple diagnosis first
diagnostic tests should be
performed first. Tech B says that
you should first question the
customer to obtain as much info as
possible about the problem
A,
B,
A & B,
Neither,
with the engine idling, a vacuum sticky valve stems and guides
gauge connected to the intake
manifold fluctuates (from 15 to 20).
These fluctuations may be caused -late ignition timing would result in a low, steady
by reading
-intake manifold leaks would cause a very low,
late ignition timing, steady reading
intake manifold vacuum leaks, -a restricted exhaust system would cause vacuum
a restricted exhaust system, to slowly decrease after the engine was
sticky valve stems and guides, accelerated and held steady
, oil is leaking from the crankshaft A&B
rear main bearing seal on an
engine. Tech A says the oil seal
could be faulty. Tech B says the
PCV system may not be
functioning.
A,
B,
A & B,
Neither,
A high-pitched squealing noise is small leak in exhaust manifold
heard during hard acceleration. This
may be the cause of: -intake manifold leak causes a high-pitched
whistle at idle and low speeds
intake manifold leak, -carb choke stuck closed will not cause a high-
the choke stuck closed pitched whistle
fuel system leak -fuel system leak normally would not cause a
small leak in exhaust manifold noise
a heavy thumping noise occurs with loose flywheel bolts
the engine idling, but the oil
pressure is normal. this may be -worn pistons and cylinders would cause a
caused by: thumping noise during acceleration
-worn main bearings cause a thump when the
worn pistons and cylinders, engine is started
loose flywheel bolts, -loose camshaft bearings would cause a
worm main bearings, growling noise at all times
loose camshaft bearings,
