ASE A2 Automatic Transmission Practice Test
21. A technician is performing a stall test on a vehicle with an automatic transmission. In Drive, the tachometer indicates the engine's RPMs are above specifications. Which of the following is causing this test result?
- A. A faulty torque converter.
- B. A clutch is slipping.
- C. The one-way stator is slipping.
- D. A restriction in the exhaust system.
Answer A is wrong. An out of balance torque converter will cause vibration during a stall test.
Answer B is correct. If the reading is above specifications, the clutches are slipping.
Answer C is wrong. If this reading is below specifications, the torque converter's stator one-way clutch is slipping, or there's a restriction in the exhaust system.
Answer D is wrong. Perform a back pressure or a vacuum test to verify a restricted exhaust. If the needle on the vacuum gauge drops steadily during acceleration, there's a restriction in the exhaust or intake system. This result is typically due to a clogged catalytic converter.
22. There's a whining noise coming from the front of an automatic transmission that increases with engine speed. This noise is present in all gears, including Park and Neutral. The MOST likely cause of this noise is the:
- A. Planetary gear set.
- B. Oil pump.
- C. Output shaft.
- D. Torque converter.
Answer A is wrong. The most likely answer is the transmission pump.
Answer B is correct. A worn transmission pump makes a whining noise that increases with engine speed in all gears, including park and neutral.
Answer C is wrong. A bad output shaft makes noise only when the transmission is in gear.
Answer D is wrong. The most likely cause is the transmission oil pump.
23. An automatic transmission slips only when cold. As the vehicle warms to operating temperature, the transmission's performance returns to normal. Which of these is causing this condition?
- A. The oil pump.
- B. Hardened seals.
- C. The torque converter.
- D. Input shaft end-play.
Answer A is wrong. The pump will usually make a whining or whirling noise.
Answer B is correct. Hardened seals allow fluid to pass the seal when cold, but as the transmission warms, the seals begin to function again. This transmission will need an overhaul to fix this problem.
Answer C is wrong. Perform a stall test to check the torque converter's performance. Always check to see if it is recommended by the vehicle manufacturer before proceeding.
Answer D is wrong. Input shaft end play would not cause this condition.
24. Technician A says to clean the valve body with solvent and a lint-free cloth. Technician B says a bent spool valve can be straightened and reused. Who is correct?
- A. Technician A
- B. Technician B
- C. Both A and B
- D. Neither A or B
Answer A is correct. The part should be cleaned in solvent and then air dried and wiped only with a lint-free cloth or towel.
Answer B is wrong. Replace bent spool valves.
Answer C is wrong. Technician A is correct.
Answer D is wrong. Technician A is correct; always use a lint-free cloth on a valve body.
25. During a transmission fluid check, the technician notices the ATF is milky in appearance. Which of these could be the cause?
- A. Overheating
- B. A slipping band.
- C. Oxidation
- D. An oil cooler leak.
Answer A is wrong. Overheating transmission fluid reduces its effectiveness dramatically.
Answer B is wrong. Slipping bands and clutches overheat the fluid causing it to turn brown colored.
Answer C is wrong. Oxidation turns the fluid a brown color.
Answer D is correct. Transmission fluid mixes with coolant in the radiator well, producing a milky color similar to a strawberry milkshake.