Five free practice questions on engine maintenance: content area A of the ASE G1 Auto Maintenance & Light Repair test, 9 of its 55 scored questions (16.4%). They are in the ASE format: four options, one best answer. Answer each one before opening the explanation. No account, no email.
01The questions
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A noise comes from the engine compartment, and its rhythm rises and falls with engine speed when the engine is revved in Park with the vehicle standing still. Any of these could be the source EXCEPT:
- a loose torque converter-to-flexplate bolt.
- a water pump bearing that has run dry.
- an exhaust manifold gasket that is leaking.
- a worn outer CV joint on a front axle.
Show the answer
D. Correct. A constant velocity (CV) joint turns only when its drive axle turns, which takes the wheels rolling; in Park with the vehicle standing still the axles are stopped however fast the engine runs. A noise that follows engine speed with the vehicle standing comes from the engine or a part it drives or shakes.
Why not the others
A. The flexplate and torque converter are bolted to the crankshaft and turn whenever the engine runs, in Park as well, so a loose bolt between them knocks in time with engine speed with the vehicle standing. It could be the source.
B. A belt-driven water pump spins with the crankshaft, so a dry, worn bearing growls or chirps faster as engine speed rises, even in Park. It could be the source.
C. Each exhaust pulse puffs through a leaking manifold gasket, so the ticking follows engine speed in Park as well as on the road. It could be the source.
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With the engine cold, a pressure tester on the radiator filler neck holds the cap's rated 15 psi for 15 minutes with no drop, yet the engine still needs coolant added every few days. Any of these could be the cause EXCEPT:
- a head gasket leak that opens only with the engine running.
- a cap that releases pressure below its rating.
- a hose joint that seeps only at running heat.
- a pinhole in a radiator tube that weeps cold or hot.
Show the answer
D. Correct. A pinhole in a core tube that weeps whether the engine is cold or hot is open whenever the system is under pressure, so the cold test at the cap's rating would have shown the gauge falling and coolant weeping from the core. A test that holds steady rules it out and points to losses that a cold, static test does not load.
Why not the others
A. Some head gasket leaks open only under combustion pressure, pushing coolant out through the overflow or letting it be burned, while the cold static test holds. A combustion leak test on the running engine checks for this.
B. The tester at the filler neck pressurizes the system with the cap off, so it does not test the cap. A cap that opens below its rating lowers the coolant's boiling point and lets coolant boil out through the overflow, so the cap is tested separately on its adapter.
C. Some joints seal cold and seep only when the parts expand at operating temperature and pressure, so a cold test can miss them. Rechecking the system hot, or with dye in the coolant, can find such a leak.
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On some engines, the A/C compressor is driven by its own multi-rib belt with no tensioner, no idler and no adjustable mounting. How is that belt kept tight on its pulleys?
- Its elastic cords hold it stretched on the pulleys
- A spring in the compressor mount pulls it tight
- Shims behind the compressor set its center distance
- Belt dressing applied at installation grips the pulleys
Show the answer
A. Correct. A stretch-fit belt is made shorter than its path around the pulleys and has elastic cords, so it is stretched on during installation and its own elasticity holds the tension. With nothing to adjust, it is installed by the manufacturer's method, usually with a special installation tool, never by prying it over a pulley flange.
Why not the others
B. A spring-loaded mount would be a tensioner, and this drive has none. The stretch-fit belt's elastic cords supply the tension themselves.
C. Shims that moved the compressor would be an adjustment, and this mounting has none. The tension comes from the stretch-fit belt itself, which is made shorter than its path and stretched on.
D. Belt dressing does not make a belt tight; it builds up in the pulley grooves and only masks slipping for a while. A stretch-fit belt is held tight by its own elastic cords.
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The manufacturer specifies a coolant mix of 50 to 60 percent ethylene glycol in distilled water. Tested with a refractometer, the coolant in the system reads 75 percent ethylene glycol. What should be done?
- Drain some coolant and add distilled water
- Leave it; the extra glycol only adds protection
- Drain some coolant and add more concentrate
- Top off the reservoir with plain tap water
Show the answer
A. Correct. At 75 percent the mix is above the manufacturer's 60 percent maximum. Glycol carries heat away less well than water, so a mix this rich cools less well, and freeze protection does not keep improving as glycol is added (straight glycol freezes at a higher temperature than the specified mix). Draining some coolant and replacing it with distilled water brings it back within 50 to 60 percent, and the refractometer is rechecked once it has circulated.
Why not the others
B. Glycol carries heat less well than water, so a mix this rich reduces cooling, and freeze protection stops improving as glycol is added and is lost as the mix nears straight glycol. The mix is brought back to 50 to 60 percent with distilled water.
C. Adding concentrate makes a mix that is already too rich richer still. The reading is above the 60 percent maximum, so water, not glycol, is added after some coolant is drained.
D. Minerals in tap water form scale and use up the coolant's inhibitors, which is why the manufacturer calls for distilled water, and a reservoir top-off adds far too little to correct a 75 percent mix. Some coolant is drained and replaced with distilled water.
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Along with a stored emission-related DTC, the scan tool shows its freeze frame data. What does the freeze frame record?
- Sensor readings at the most recent key-on
- Engine conditions at the moment the DTC set
- The readiness status of each monitor
- The number of trips since DTCs were cleared
Show the answer
B. Correct. When the DTC sets, the PCM stores a snapshot of the engine conditions at that moment, such as engine speed, calculated load, coolant temperature, vehicle speed and open- or closed-loop status. Recording it before codes are cleared lets the technician recreate those conditions on a road test to reproduce the fault and to confirm the repair.
Why not the others
A. Freeze frame is captured at the moment the fault was detected, which may have been days ago at highway speed; it is not a picture of the latest key-on. Live data shows current values.
C. Readiness status, which shows whether each monitor has run since the codes were cleared, is a separate screen. Freeze frame is the snapshot of conditions when the DTC set.
D. The count of warm-ups or distance since codes were cleared is separate data. Freeze frame is the snapshot of engine conditions at the moment the DTC set.
02Answer key
| Question | Answer |
|---|---|
| Q1 | D |
| Q2 | D |
| Q3 | A |
| Q4 | A |
| Q5 | B |
03What area A covers
This content area covers routine engine service and inspection: verifying a concern, finding leaks and noises, oil and filter changes, the cooling system from hoses and belts to thermostats, pumps, fans and coolant, air filters and throttle body cleaning, PCV parts, exhaust hangers and heat shields, spark plugs, fuel lines and filters, EVAP parts, reading DTCs and topping up diesel exhaust fluid.
The ASE test specification calls this content area “Engine Systems”. It carries 9 of the 55 scored questions, 16.4% of the test.
- Verify concerns and inspect for leaks and noises
- Change oil and filter and reset the oil life monitor
- Test and service the cooling system and coolant
- Inspect and replace belts, tensioners and hoses
- Service air filters, throttle bodies and PCV parts
- Inspect exhaust hangers, heat shields and leaks
- Replace spark plugs and external fuel filters
- Read DTCs, check EVAP parts and refill DEF
04What the questions turn on
Normal coolant level changes
Coolant expands as it heats and passes the cap into the recovery reservoir, and the cap's vacuum valve draws it back as the engine cools. A reservoir at its hot mark after a drive and its cold mark in the morning is normal.
Refill and bleed the system
Filling at the radiator neck with the engine off can leave air in the head, around the thermostat and in the heater core. The engine then overheats while the heater blows cold, so the system is refilled and bled as the manufacturer directs.
Oil level after a filter change
The empty new filter and the drained oil passages fill on the first run, so a level read right after filling looks higher than it will be. The engine is run briefly, shut off and given a few minutes before the dipstick is read.
Fix the leak before the belt
Oil softens and swells a belt's rubber and makes it slip. The oil leak is repaired and the pulley grooves are cleaned dry before a new belt goes on, or the new belt soon fails the same way.
05The other content areas
The G1 test has seven content areas. Each has its own page of free questions:
The ASE G1 Auto Maintenance & Light Repair practice test page describes the full question bank. How these questions are written and checked: how our questions are made. Found a mistake? Tell us and we will fix it.
ToolboxPrep is an independent study site. It is not affiliated with or endorsed by ASE (the National Institute for Automotive Service Excellence). Our questions are original practice questions written to the published ASE test specifications; they are not actual test questions.