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141 Cards in this Set
- Front
- Back
Tech A: the most complicated diag tests should be done first
Tech B: The customer complaint must be identified |
B (only
Verify complaint and perform simplest tests first) |
|
A throttle body injected engine has no-start complaint and no fuel from the injectors while cranking:
Tech A: check voltage supply to fuel pump Tech B: Fuel filter may be restricted |
A
(a partially restricted fuel filter will allow SOME fuel to pass zero fuel pressure can result from no voltage to pump) |
|
A pressurized cooling system is pressurized to locate a coolant leak. it drops from 10 psi with no visible leaks under the hood:
A: leaking head gasket, B: heater core |
C
(Both leaks will not show up in engine compartment, but will reduce pressure) |
|
a heavy thumping noise at idle, Oil pressure is normal:
A: worn pistons and cylinders B: loose flywheel bolts C: worn main bearings D: Loose camshaft bearings |
B
(Loose flywheel bolts can cause a thumping at idle) |
|
A port fuel injected engine has a steady puff noise in the exhaust at idle.
A: burned exhaust valve B: Excessive fuel pressure C: A restricted fuel line D: A sticking fuel pump check valve |
A
(A burned exhaust valve causes a "puff") |
|
with the engine idling, the vacuum gauge to the intake manifold fluctuates from 12-18"
A: late ignition timing B: Intake manifold vacuum leaks C: a restricted exhaust D: Sticky Valves |
D
(Sticking Valves cause a fluctuation between 12 and 18" at idle) |
|
During a Cylinder balance test, #3 cyl provides very little rpm drop
A:ignition system may be misfiring on #3 B: The engine may have an intake manifold vacuum leak |
C
(Both are correct very little rpm drop indicates a misfire, which may be caused by a vacuum leak) |
|
During a compression test, a cyl has 40% of the specified reading. During the wet test the reading is 75%.
A: burned exhaust valve B: worn piston rings C: Bent intake valve D: worn camshaft lobe |
B
(Worn piston rings. If compression increases significantly from dry to wet tests, this indicates worn rings and cylinders) |
|
During a leakage test cyl #2 has 50% leakage and air is escaping from the pcv opening
A: intake valve in #2 may be leaking B: #2 may have worn rings |
B
(Worn rings cause air to escape from into the crank case and out through the pcv opening) |
|
A: a steel scraper should be used to clean the gasket surfaces on aluminum cylinder heads
B: Some manufacturers provide a de-torque sequence for head bolts in aluminum heads |
B
(Some manufacturers do provide a de-torque sequence) |
|
A: when checking cylinder head warpage, the straightedge should be held straight across lengthwise down the center
B: when checking cylinder head warpage, the straightedge should be held diagonally at two locations |
B
|
|
A: during free length test the valve spring must be held in one position
B: During free length test the valve spring must be rotated to check for vairance of more than 1/8 inch |
D
(During free length test, the valve spring must be rotated to check for variance of more than 1/16 inch) |
|
A: valve spring tension should be measured at installed height
B: If a shim is to be used under the spring, it should be installed under the spring on the tension guage |
C
(Both statements are correct) |
|
A: worn valve lock grooves may cause the valve locks to fly out of place with the engine running and cause severe damage
B: worn valve lock grooves may cause a clicking noise with the engine idling |
A
(worn valve lock grooves will not cause a clicking noise because they are continuously loaded by spring tension.) |
|
A: worn valve stem seals may cause rapid valve stem and guide wear
B: Worn valve stem seals may cause excessive oil consumption |
B
(worn seals will allow oil to leak by into the cylinder but will not increase stem and guide wear) |
|
A: Valve stem and guides should be measured at three vertical locations
B: The valve guide diameter should be measured with a hole or snap guage |
C
|
|
If the valve stem-to-guide clearance is more than specified, what may be done instead of replacement of the guide?
|
the guide may be knurled, or bored out with a thin-wall liner installed
|
|
a valve margin of 1/64" may cause:
A: a clicking noise at idle B: a valve overheating and burning C: improper valve seating D: Valve seat recession |
B
(1/64" is less than standard valve margin and may result in overheating and burning) |
|
Tech A: Valve tips can be resurfaced on a valve grinder
Tech B: Valve overheating can occur if the valve margin is less than 1/32" |
C
|
|
Valve seats are typically ground to an angle of:
A: 15 or 20 degrees B: 20 or 30 degrees C: 30 or 45 degrees D: 45 or 60 degrees |
C
(Most valves are ground to an angle of 30 or 45 degrees) |
|
A; a 60 deg grinding stone should be used to raise valve seat contact area
B: Low valve seat contact area on the valve face may cause a clicking noise at idle |
A
(a 60 and 45 degree grinding stone is used to raise the seat contact area) |
|
installed valve spring height is more than specified:
A: this may bottom out the lifter plunger B: a shim should be installed under the valve spring |
B
(A shim may be used to reduce INSTALLED valve spring height. bottoming out of the lifter plunger is directly related to valve STEM height, and not necesarily valve spring height) |
|
Tech A: excessive valve spring tension may cause bent pushrods
Tech B: improper valve timing may cause bent pushrods |
C
(Both problems may result in bent pushrods, as well as sticking valves. Improper timing on interference engines may cause the valves to hit the piston, bending the rods) |
|
A: hydraulic valve lifter bottoms should be flat or concave
B: a sticking lifter plunger may cause a burned exhaust valve |
B
(lifter bottoms should be CONVEX. a sticking lifter plunger may hold the valve open and burn the valve) |
|
Mechanical valve lifters:
A: when the valve clearance is checked on a cylinder, the piston should be at TDC Exhaust B: some mechanical valve lifters have removable ship pads available in various thicknesses to provide the proper clearance. |
B
(when checking valve clearance the piston must be at TDC COMPRESSION. B is correct) |
|
when the timing gear teeth mesh directly with crank gear teeth:
A: timing gear backlash can be checked with a dial indicator B: on this type of engine the timing gear backlash may be checked with a micrometer |
A
|
|
A:Excessive cam bearing clearance may result in low oil pressure
B: excessive cam bearing clearance may cause a thumping noise at idle |
A
|
|
A: Improper valve timing may cause reduced engine power
B: improper valve timing may cause bent valves in some engines |
C
|
|
A: torque to yield bolts provide more uniform clamping force
B: T-T-Y bolts are tightened to a specific torque, and then turned a certain number of degrees |
C
|
|
all of the following are true EXCEPT
A: the ring ridge should be removed before removing the pistons and connecting rods B: The connecting rods must be re installed with their markings facing in the specified direction C: The main bearing caps must be installed in their original position D: after ridge reaming, use compressed air to blow the metal filings from the cylinders |
D
|
|
A: Warped cylinder head mounting surface on an engine block may cause valve seat distortion
B: warped cylinder head mounting surface on an engine block may cause coolant and combustion leaks |
C
|
|
A: the first step in heli coil installation is to use a tap and thread the opening to match the external threads on the helicoil
B: the helicoil should be installed with the proper sized drill bit |
D
|
|
if new rings are installed without removing the ring ridge, the following may result:
A: the piston skirt may be damaged B: the piston pin may be broken C: the connecting rod bearings may be damaged D; the piston ring lands may be broken |
D
|
|
A: Cylinder taper is the difference between the cyl diameter at the top of ring travel compared to the center of ring travel
B: Cylinder out of round is the difference between the axial cyl bore at the top of ring travel compared to the thrust cyl bore at the bottom of ring travel |
D
|
|
When deglazing and cleaning a cylinder:
A: 120 grit stones can be used on the cylinder bore B: Wash the cylinder with soapy water after deglazing C: Wash the cylinder with an oil based solvent after de-glazing D: 400 grit emery paper and hand pressure may be used |
B
(use soapy water and a bristle brush after deglazing) |
|
Which grit stones should be used for deglazing a cylinder?
|
220 or 280
|
|
how should out of round be measured on crank journals?
|
at two locations on each side of journal
|
|
main bearing bore alignment may be measured with:
A: a dial indicator B: a micrometer C: a telescoping gauge D: a straightedge and a feeler gauge |
D
|
|
a crankshaft has more than specified endplay:
A; the thrust surfaces on the sides of one main bearing may be worn B: a thicker shim should be installed between the rear edge of the rear man bearing and the rear crank flange |
A
|
|
an engine block service tool is used to:
A: remove cam bearings B: install Cam bearings C: remove and install cam bearings D: measure cam bearing alignement |
C
|
|
A: improper balance shaft timing causes severe engine vibration
B: Balance shafts are timed in relation to the camshaft |
A
|
|
a piston service tool is used to:
A: widin the piston ring grooves B: deepen the piston ring grooves C: remove and replace piston rings D: remove carbon from the ring grooves |
C
|
|
Bent connecting rods may cause:
A: uneven connecting rod bearing wear B: uneven main bearing wear C: uneven piston pin wear D: excessive cylinder wall wear |
A
|
|
A: curvature of connectin rod bearings is slightly larger than the curvature of the bearing bores, this is called bearing spread
B; when a connecting rod bearing half is installed the bearing edges extend slightly from the mounting area and this feature is called bearing crush |
C
|
|
A: Ring gap should be measured with the ring positioned at the top of the ring travel in the cylinder
B: the two compression rings are interchangeable on most pistons. |
D
|
|
A: The vibration dampener counterbalances the back and forth twisting motion of the crankshaft each time a cylinder fires
B: if the seal contact area on the vibration damper hub is scored, the damper assembly must be replaced |
A
(the dampener can sometimes be machined and re-installed) |
|
A: Metal burrs on the crankshaft flange may cause excessive wear on the ring gear and starter drive gear teeth
B: Metal burrs on the crankshaft flange may cause improper torque converter to transmission alignment |
C
|
|
A: excessive flywheel runout may cause grabbing, erratic clutch operation
B: the pressure plate should always be reinstalled in the original position on the flywheel |
C
|
|
a worn pilot bearing may cause a growling, rattling noise
A: while driving at a steady 20 mph B: in reverse with the clutch engaged C: while accelerating in low gear D: With the clutch pedal pressed |
D
|
|
A: A springless seal may be used in the timing gear cover
B: when a seal is installed the seal lip must not face towards oil. |
D
(the timing gear cover seal must always have a garter spring, and the lip must face the oil) |
|
RTV sealer
A: the components to be sealed should be washed with an oil based solvent B: an RTV bead 1/8 in. wide should be placed in the center of the sealing surface C: the RTV bead should be placed on one side of any bolt holes D: the RTV bead should be allowed to dry for ten minutes before component installation |
B
|
|
All of the following cause low engine oil pressure EXCEPT:
A. worn cam bearings B. worn crank bearings C. weak oil pressure regulator spring tension D. restricted pushrod oil passages |
D
|
|
The following are normal oil pump component measurements EXCEPT:
A. inner rotor diameter B. clearance between rotors C. inner and outer rotor thickness D. outer rotor to housing clearance |
A
( is not a normal measurement, if rotor clearances are normal, there is no reason to measure the inner rotor diameter) |
|
a pressure tester may be used to test the following EXCEPT:
A. cooling system leaks b. radiator cap pressure relief valve C. the coolants specific gravity D. heater core leaks |
C
|
|
in a drive belt system, where one belt drives only the alternator, a loose alternator belt may cause:
A. a discharged battery B. a squealing noise when decelerating C. a damaged alternator bearing D. Engine overheating |
A
|
|
A: a collapsed upper radiator hose may be caused by an in-op pressure release valve on the radiator cap
B: a collapsed upper radiator hose may be caused by a plugged hose between the radiator filler neck and the recovery resevoir |
B
( a plugged recovery reservoir hose prevents coolant from the surge tank back into the radiator as the engine cools down, causing a vacuum and a collapsed upper hose) |
|
the thermostat is stuck open on a port fuel injected engine. this may cause:
A. a rich air fuel ratio B. a lean air fuel ratio C. excessive fuel pressure D. engine overheating |
A
( an open thermostat keeps the engine temp low. the ECM will command more fuel due to the lower temp, creating a rich A/F ratio) |
|
A: if the cooling system pressure is reduced the coolant boiling point is increased
B; when more antifreeze is added to the coolant the coolant boiling point is in creased |
B
(when the pressure is reduced, so is the boiling point) |
|
A: a damaged water pump bearing may cause a growling noise when the engine is idling
B: the water pump bearing may be ruined by coolant leaking past the pump seal |
C
|
|
an excessively high coolant level in the recovery reservoir may be caused by any of the following EXCEPT
A: restricted radiator tubes B: a thermostat that is stuck open C: a loose water pump impeller D; an in-op electric drive cooling fan |
B
(a stuck open t-stat will not cause a high level in the surge tank) |
|
an engine oil cooler helps to prevent
A. oxidation of the engine oil B. excessive oil pressure C. oil pump wear D. main bearing wear |
A
( by keeping the oil cool, it is preventing oil oxidation) |
|
A: an intake manifold vacuum leak may cause a cylinder misfire with the engine idling
B: an intake manifold vacuum leak may cause a cylinder misfire during hard acceleration |
A
(an intake manifold leak will not cause misfire during hard acceleration because there is less vacuum) |
|
while cleaning a pleated paper type air filter element the air gun should be held
A: 6 in from the outside of the filter B. directly against the outside of the element C. directly against the inside of the element D. 6 in from the inside of the element |
D
|
|
reduced turbo boost may be caused by:
a: a stuck closed wastegate valve B. a stuck open wastegate valve C. a leaking wastegate diaphragm d. a disconnected wastegate linkage |
B
( the rest will cause an increase in turbo pressure) |
|
During a battery test with a VAT 40:
A. the battery should be discharged at 2/3 CCA B. the battery should be discharged at 1/2 amp hour rating C. The voltage should remain above 9.6 V at 70 deg F D. The load should be applied to the battery for 20 seconds |
C
|
|
A: the neg battery cable must be removed prior to starter removal
B; if there are shims between the starter mounting flange and the flywheel housing, these shims should be discarded when the starter is re-stalled. |
A
|
|
a restricted PCV to intake hose is restricted, this could cause:
A. an acceleration stumble B: oil accumulation in the air cleaner C. engine surging at low speed D. Engine detonation during acceleration |
B
(Excessive crank case pressure will force air through the clean air hose and oil buildup on the air cleaner) |
|
All of the following statements about manifold heat control valves are true EXCEPT:
A a manifold heat control valve improves fuel vaporization in the intake manifold, especially when the engine is cold B: a manifold heat control valve stuck closed causes a loss of engine power C: a manifold heat control valve stuck open causes an acceleration stumble D: a manifold heat control valve stuck closed reduces intake manifold temperature |
D
|
|
A manifold heat control valve:
A: provides heat to the manifold in the open position B: provides heat to the manifold in the closed position |
B
|
|
Noises:
a rapping noise while accelerating |
worn pistons and cylinders
|
|
Noises:
thumping noise when the engine is started, low oil pressure |
Worn main bearings
|
|
Noises:
loose cam bearings |
do not usually cause a noise
|
|
Noises:
Loose flywheel bolts |
a thumping at idle
|
|
T/F
excessive fuel pressure or a restricted return line causes a lean condition |
F
|
|
T/F
a sticking fuel pump check valve may cause hard starting |
T
|
|
T/F
a burned exhaust valve causes a "puff" noise in the exhaust |
T
|
|
T/F
late ignition timing causes a low steady vacuum gauge reading |
T
|
|
T/F
a restricted exhaust system causes a high vacuum reading at high speed |
F
|
|
If the compression increases significantly from a dry to wet compression test...
|
worn rings and cylinders are indicated
|
|
Worn rings cause air to escape from (...) during cylinder leakage test.
|
the PCV opening
|
|
leaking intake valves cause air to escape from (...) during cylinder leakage test.
|
the intake
|
|
a (...) scraper should be used to clean gasket surfaces on aluminum heads
|
Plastic
|
|
The valve spring must be (...) while measuring height and squareness
|
Rotated
|
|
T/F
worn valve spring locks will cause a clicking noise |
F
|
|
most valve seats have an angle of (...or...) degrees
|
30 or 45
|
|
T/F
improper valve seat contact area on the valve face causes a clicking noise at idle |
F
|
|
When the valve seat contact area is too low (...&...) degree stones are used to move it upward
|
60 & 45
|
|
lifter bottoms must be (...)
|
convex
|
|
Cam lobe lift can be measured with a dial indicator positioned against the top of the (...)
|
Pushrod
|
|
T/F
excessive cam bearing clearance causes a thumping noise |
F
|
|
Ring ridge should be removed (...) extracting the pistons
(Before or After) |
Before
|
|
T/F
Connecting rods may be installed in any position |
F
|
|
T/F
Main bearings must be re-installed in their original position |
T
|
|
after ridge reaming (...) must be used to clean the metal shavings
|
an oily rag
|
|
cylinders may be deglazed with (...-...) grit stones
|
220-280
|
|
If the valve seat is too high, (...&...) degree stones are used to lower it
|
30 & 45
|
|
ring gap should be measured with the ring at the (...) of ring travel
(top/bottom/center) |
Bottom
|
|
pilot bearing inner and outer races turn at the same speed and cannot make noise when the clutch is (...).
|
engaged
|
|
RTV sealer cures in (...) minutes
|
Five
|
|
(...) solvents must be used to clean RTV sealed components,
|
Chlorinated
|
|
Engine vacuum is highest with the throttle (...).
(open/closed) |
closed
|
|
during a battery load test the battery should be discharged at (...) CCA.
|
half
|
|
during a battery load test the battery should be discharged for (...) seconds
|
15
|
|
Battery voltage should remain above (...)V at 70 degrees during testing
|
9.6V
|
|
A defective or sticking valve lifter causes a (...) noise that is most noticeable when the engine is (...)
|
clicking noise,
First started |
|
worn main bearings cause a (...) noise when the engine is (...)
|
thumping noise
first started |
|
loose connecting rod bearings cause a (...) noise when the engine is (...)
|
clattering
accelerated and decelerated |
|
Blue exhaust indicates
|
Oil consumption
|
|
Black exhaust indicates
|
a rich condition (excessive fuel consumption)
|
|
Gray exhaust indicates
|
coolant in the combustion chamber
|
|
Noises:
a puff noise at the exhaust usually indicates |
a misfire
|
|
Noises:
erratic pulses at the exhaust usually indicates |
a rough idle caused by ignition or fuel systems
|
|
Noises:
a high pitched squeal during hard acceleration may be caused by |
a leak in the exhaust, especially at the manifold or pipe.
|
|
noises:
an intake manifold leak causes a (...) |
high pitched whistle at idle and low speeds.
|
|
vacuum gauge at idle:
low steady vacuum readings indicate |
late ignition timing
|
|
vacuum gauge at idle:
excessively low steady reading may indicate |
a manifold leak
|
|
vacuum gauge at idle:
fluctuation from 11-16 in on carbureted engine indicates |
idle mixture screws need adjusting
|
|
compression test:
low compression on two adjacent cylinders may indicate: |
a leaking head gasket or cracked cylinder head
|
|
compression test:
higher than specified compression may indicate: |
Carbon deposits in the combustion chamber
|
|
when testing valve spring free length, a variance of (...) indicates a bent spring that must be replaced
|
1/16 in.
|
|
Valve seats are typically ground to an angle of
|
30 or 45 degrees
|
|
60 and 45 degree stones are used to (...) the valve seat contact area
|
raise
|
|
sticking lifter plungers cause a (...) noise
|
clicking
|
|
30 and 45 degree stones are used to (...) the valve seat contact area
|
lower
|
|
many overhead cam engines don't have (...) camshaft bearings
|
removeable
|
|
A fully charged battery should have a specific gravity of (...)
|
1.265
|
|
during a battery load test, the battery is discharged at half CCA for (...) seconds
|
15
|
|
the engine makes a clattering noise when accelerating and decelerating what is the most likely cause of this problem?
|
loose connecting rod bearings
|
|
The bearing inserts in a connecting rod have a V-shaped wear pattern, and the attached piston has uneven wear on the piston skirt. the most likely cause:
A. a worn connecting rod bearing B. excessive piston clearance C. Worn piston rings D. a connecting rod misalignment |
d
|
|
an ignition system experiences repeated module failure, the most likely cause is:
A. shorted primary winding b. a shorted secondary winding C. an open pickup coil D. a leaking distributor cap and rotor |
A
(secondary winding, pickup coil, or leaking cap and rotor don't affect the module) |
|
most likely cause of a high pitched squealing noise only at idle
|
an intake leak
|
|
Noises:
Clattering while accelerating and decelerating |
Loose or worn connecting rod bearings
|
|
when there is no spark at any of the plugs on a coil near plug system, the (...) may be defective
|
Crankshaft sensor
|
|
vacuum gauge at idle:
fluctuation from 11-16 in on an EFI engine indicates |
injectors need cleaning or replacing
|
|
Sticking valves may cause vacuum gauge fluctuation between (...&...) at idle
|
14 &18 in.
|
|
vacuum gauge at idle:
burned or leaking valves cause gauge fluctuations between: |
12 &18 in
|
|
vacuum gauge at idle:
weak valve springs result in vacuum gauge fluctuation between: |
10 & 25 in
|
|
vacuum gauge at idle:
a leaking head gasket may cause vacuum gauge fluctuations between: |
7 & 20 in
|
|
vacuum gauge At idle:
sticking valves can cause vacuum gauge fluctuations between: |
14 &18 in
|
|
vacuum gauge At idle:
a steady, but much lower than normal reading |
an intake manifold leak
|
|
vacuum gauge At idle:
a normal reading should hold steady and between (...) |
17 & 22 in
|