ASE Certified Mechanics Practice Test Video Answers

1. B
Excessive hydraulic lifter leak down allows the lifters to collapse overnight causing a ticking noise when the engine is cold and once oil pressure builds the noise disappears while worn main bearings cause continuous thumping loose flywheel bolts cause heavy idle noise and a worn timing chain rattles constantly.

2. C
Air escaping from the tailpipe during a cylinder leakage test indicates a leaking exhaust valve while air from the carburetor or throttle body indicates an intake valve leak and bubbles in the cooling system indicate a head gasket leak.

3. B
A voltage drop of 0.87 volts during cranking indicates high resistance in the positive battery cable since normal voltage drop should be under 0.5 volts and excessive resistance reduces current to the starter.

4. B
The battery must be checked first in a no crank diagnosis because a fully charged battery has 12.6 volts and other starter components cannot function correctly without proper battery condition.

5. C
Air in the hydraulic system causes a spongy brake pedal because air compresses while brake fluid does not which delays brake pressure application.

6. D
A seized right front caliper causes the vehicle to pull left during braking because the left brake applies more force while a seized left caliper would cause a pull to the right.

7. A
An illuminated amber ABS light indicates an ABS system fault and the system reverts to normal braking without antilock capability while the parking brake only affects the red brake warning light.

8. A
A faulty master cylinder causes a low fading pedal while a hard pedal is usually caused by loss of power assist such as booster or vacuum issues.

9. B
Double walled copper tubing should never be used for brake lines because it corrodes and expands under pressure while double flared steel tubing is the correct material.

10. B
A worn right front wheel bearing produces a growling noise that increases with speed and becomes louder during left turns due to increased load on the right side.

11. D
Worn stabilizer bar bushings allow excessive body roll because the stabilizer bar cannot effectively resist body lean during cornering.

12. B
On MacPherson strut suspension a spring compressor is not required to separate components but wheel alignment must always be checked after suspension work.

13. C
A vehicle drifts toward the side with less caster so more positive caster on the left causes a drift to the right and caster does not cause tire wear.

14. B
Caster provides directional stability and steering wheel return because positive caster creates a self centering effect.

15. C
Both technicians are correct because variable assist steering uses vehicle speed input to reduce assist at higher speeds and a faulty signal causes loose steering.

16. B
During a battery capacity test voltage should not drop below 9.6 volts at 70 degrees Fahrenheit when loaded to half the cold cranking amps.

17. B
Technician B is correct because voltage drop testing is performed during cranking and the battery should be approximately 75 percent charged.

18. A
A whining noise during starter engagement is typically caused by a defective starter drive that does not mesh properly with the flywheel.

19. B
Headlights that brighten with engine speed indicate high charging voltage usually caused by a faulty voltage regulator allowing excessive alternator output.

20. B
In a series circuit current remains the same throughout because there is only one path for current flow while voltage is divided.

21. D
A cool suction line at the compressor is normal operation while a stuck valve or low refrigerant would cause abnormal temperatures.

22. D
The accumulator is located on the low pressure side between the evaporator and compressor and prevents liquid refrigerant from entering the compressor.

23. C
Reduced AC performance at idle is caused by airflow issues at the condenser such as debris or cooling fan problems not a frozen expansion valve.

24. B
Electronic leak detection should be performed from bottom to top because refrigerant is heavier than air and settles downward.

25. C
Hybrid vehicles use POE oil in AC compressors because it is non conductive and safe for high voltage systems.

26. B
A resistance reading of zero ohms indicates a shorted compressor clutch coil while normal resistance is typically between two and five ohms.

27. C
Both technicians are correct because a cylinder with little RPM drop during a balance test is not contributing power due to misfire or vacuum issues.

28. D
A fluctuating vacuum gauge reading at idle indicates a lean mixture while timing problems produce steady abnormal readings.

29. B
Checking cylinder head squareness is not standard during head gasket replacement while checking warpage cleaning bolt holes and inspecting for leaks is required.

30. A
Camshaft lift is the difference between the base circle diameter and maximum lobe height which determines valve opening distance.

31. B
Excessive camshaft endplay is most commonly caused by a worn thrust plate which controls camshaft movement.

32. B
Hydro boost brake systems rely on power steering pressure so reduced braking requires checking the power steering system first.

33. A
Technician A is correct because some ABS systems contain high pressure accumulators that must be discharged before service to prevent injury.

34. A
Brake drums machined beyond maximum diameter are prone to mechanical fade because thinner drums expand more when heated.

35. C
Excessive inside tire wear indicates too much negative camber which increases contact pressure on the inner tread.

36. C
Power steering systems should be flushed only with approved power steering fluid or cleaner and never with brake or carburetor cleaners.

37. C
Electric power assist steering does not use a hydraulic pressure switch and instead relies on speed angle and torque sensor inputs.

Electric vehicle technician candidates often also prepare with our ASE practice test 2026 for the automotive electrical and diagnostic skills both technician certifications share.