The Driven to Win quiz is your chance to qualify for the 2023 U.S. Auto Tech National Championship. It is a fast-paced five-minute digital challenge that will test you on overall vehicle knowledge. The highest professional and student score from this month's quiz will automatically advance to the championships in Tampa, FL
You are limited to one quiz attempt per day, and you will not be able to go back to a question once you've submitted your answer.
An engine’s upper and lower center main bearings show more wear than the ones toward either end of the crankshaft.
Technician A says this wear pattern could be due to a bent crankshaft and replacing it with one that is straight will fix the problem.
Technician B says the cylinder block main bearing bores are mis-aligned and the problem can be fixed by align boring or honing the block.
A cylinder head is being prepared for resurfacing. Technician A says if a core plug appears OK, then it should be left in place. Technician B says all studs must be removed.
Who is correct?
Technician A says main bearing oil clearance can be checked with Plastigage. Technician B says main bearing oil clearance can checked with a dial bore gauge
An engine’s upper and lower center main bearings show more wear than the ones toward either end of the crankshaft. Technician A says this wear pattern could be due to a bent crankshaft and replacing it with one that is straight will fix the problem. Technician B says the cylinder block main bearing bores are mis-aligned and the problem can be fixed by align boring or honing the block.
Technician A says the seals on a GDI (Gasoline Direct Injection) injector can be reused after the injector is removed from the cylinder head. Technician B says when MPI (Multi Port Injection) injector o-rings leak, there will be a compression loss in the cylinder.
Automatic transmission oil pumps are being discussed. Technician A says vane or gear type oil pumps, both create an area of low pressure within the inlet chamber as the pump turns. Technician B says vane or gear type oil pumps provide a variable level of output fluid volume.
An engine coolant temperature (ECT) sensor is being tested. Technician A says that a Negative Temperature Coefficient (NTC) Sensor can be tested by checking the voltage drop across the sensor. Technician B says that resistance within the sensor will go up when the engine coolant temperature is cold on this type of sensor.
A magneto resistive/analog vehicle speed sensor (VSS) is being tested. Technician A says that the transmission shaft should be rotated while checking for DC voltage output. Technician B says the sensor resistance should be checked.
Technician A says the fluid level on some automatic transmissions is checked by removing a level control plug. Technician B says in the case of a level control plug, the fluid level should be checked with the engine off.
Technician A says that, when testing transmission actuator solenoids, a normally closed solenoid should block air flow when energized. Technician B says that a normally open solenoid should allow air flow when energized.
When inspecting a planetary gear set, Technician A says that the pinion gear side clearance should be checked with a feeler gauge. Technician B says that if any part of the planetary gear set fails inspection, the entire gear set must be replaced.
Technician A says that transaxle final drive side bearing preload is typically measured with an inch pound torque wrench. Technician B says that all end-play must be removed when adjusting bearing preload.
After removing a transmission from a vehicle, inspections should be performed. Technician A says the rear main seal and engine block core plugs should be inspected for leakage. Technician B says the flex plate and transmission alignment dowel pins should be inspected for damage.
With the clutch pedal fully depressed and the transmission is in gear, a noise is heard coming from the bell housing area. Technician A says the noise could be caused by a worn pilot bushing. Technician B says that the noise is probably due to a defective transmission input shaft.
Technician A says that if a transmission is hard to shift into gear, the problem is likely in the clutch.
Technician B says that hard shifting can be caused by binding shift linkage or synchronizers.
Two technicians are installing a transmission in a rear wheel drive vehicle and the transmission case will not seat against the bellhousing.
Technician A says that since its close you can draw it into place with the mounting bolts.
Technician B says that the transmission should be removed and the clutch disc alignment should be rechecked.
Technician A says that engine/transmission misalignment can cause a pulsation in the clutch pedal.
Technician B says that dowel pins are only necessary to mate the transmission and engine together during factory assembly.
A (RWD) rear wheel drive vehicle with a one-piece driveshaft has excessive driveshaft vibration during low speed acceleration.
Technician A says the vibration could be caused by binding U-joints.
Technician B says improper driveshaft angle could be the cause.
Two technicians are discussing axle shafts and bearings.
Technician A says an axle shaft that rides on straight roller bearings and is retained with C-clips may require replacement if there is excessive radial (up and down) play.
Technician B says an axle shaft with sealed ball bearings that is attached with a retaining plate may have to be shimmed to set preload/end play.
Two technicians are discussing replacement of a rack and pinion assembly on a vehicle equipped with an airbag. Technician A states to center the steering before disconnecting the steering shaft coupler and to center the new steering gear before installation. Technician B states to disconnect the battery or remove power from the airbag module before replacing the rack and pinion.
A vehicle with power steering exhibits poor assist in one direction and a pressure tester has been installed. When the wheels are steered full lock, the pressure tester readings in one direction are lower than the other. With the shut off valve closed, the readings are normal. Technician A says that these readings could be caused by a bad steering gear. Technician B says that these readings could be caused by a bad pump.
Technician A says that a bent idler arm can cause bump steer. Technician B says that a worn rack mount bushing could cause bump steer.
Technician A says that horizontal looseness in a Pitman arm stud can cause a vehicle to wander at highway speeds. Technician B says vertical movement in an idler arm can cause toe change.
A vehicle that had a lower control arm replaced returns with suspension noise and failed bushings in the new lower control arm.
After an accident, a steering knuckle has a damaged tapered hole where the ball joint attaches.
What would be the proper repair?
A vehicle wanders while being driven on level roads. Technician A says excessive toe out could be the cause. Technician B says too much positive caster could be the cause.
The alignment readings listed below could result in which of these conditions?
While testing a starting circuit, the technician finds that the engine cranks slowly. The starter current draw is 80 amps and the battery voltage while cranking is above 11 volts.
What should the technician do next?
An ohmmeter is being used to check a circuit for continuity. Technician A says an infinity or “OL” reading indicates no continuity. Technician B says a zero reading on an ohmmeter indicates continuity.
Who is right?
Technician A says a short circuit to ground in a circuit will decrease resistance. Technician B says a short circuit will increase current flow.
During an A/C system performance test, the air temperature at the center outlet duct is warm to slightly cool. The low side gauge is reading lower than normal and the high side gauge, at the compressor, is reading lower than normal. Technician A says to check for a clogged orifice tube. Technician B says to check for a plugged condenser.
During an A/C system performance test, high side pressure was found to be exceeding the high-pressure switch’s protection limit and the A/C compressor continued to run.
Technician A says that the high-pressure cutout switch could be defective.
Technician B says that there could be an air flow obstruction at the evaporator.
During A/C system operation, a knocking sound can be heard coming from the compressor. Technician A says that there could be internal compressor damage.
Technician A says that the pressure cycling switch is usually located on the accumulator.
Technician A says the ambient temperature switch protects the compressor from damage.
Technician B says the ambient temperature sensor provides input for the Automatic Temperature Control (ATC) system.
When troubleshooting an Automatic Temperature Control (ATC) system, the system responds when the ambient and in-vehicle temperature sensors are heated and cooled. However, there is no response when the sun load sensor is exposed to a fluorescent light source.
Technician A says that the problem is with the ATC system programming.
Technician B says that the problem is with the sun load sensor.
A customer brings their vehicle in for service. They describe symptoms of poor drivability and state that the vehicle has been repaired for the same problem in the past.
What should you do first?
Two technicians are listening to a tapping noise coming from the top end of a V8 engine.
Technician A says the noise could be a valve in need of adjustment.
Technician B says the noise could be an exhaust leak.
A vehicle's exhaust system is being tested for a restriction using a vacuum gauge, connected to the intake manifold.
Technician A says a vacuum level that drops 3 in. Hg below the original reading when accelerating to 2500 RPM and holding for a few minutes indicates a restricted exhaust.
Technician B says if vacuum does not increase when closing the throttle from 2000 RPM it indicates a restricted exhaust.
Technician A says an incorrect CKP (Crankshaft Position Sensor) gap can cause a misfire.
Technician B says when testing two wire CKP with an ohmmeter, the meter should read infinity when the ohmmeter is connected between the pins in the connector.
A vehicle is towed in with a 'cranks but won't start' condition. A 'noid' light test finds no injector pulses and there is no spark present at any of the plug wires.
Technician A says the vehicle needs a computer.
Technician B says the vehicle needs an ignition module.
Technician A says with the vacuum line connected to the fuel pressure regulator; fuel pressure should be higher than with the line disconnected.
Technician B says some fuel pressure regulators can suffer from a ruptured diaphragm, allowing fuel to be sucked into the intake manifold through the vacuum line causing a rich running condition.
On a gasoline engine, the Camshaft Position Sensor (CMP) signal has failed and set a DTC. Technician A says the ECM/PCM will command the camshaft timing to freeze in the last valid commanded position. Technician B says both the commanded and actual CMP PIDs will indicate 0 Degrees on the scan tool.
A diesel engine has White smoke coming from the exhaust. Technician A says a leaky Injector could be the cause. Technician B says it could be a dirty Injector.
On a cold winter morning, a diesel engine vehicle will not start. Technician A says using number one grade diesel fuel could be the cause. Technician B says using number two fuel could be the cause.
Technician A says in an Electronic Unit Injector (EUI) fuel system, the injection pressure is created by the force provided by the engine’s camshaft, but the quantity of fuel injected is controlled by the PCM/ECM powering the injector solenoid.
Technician B says in a Pump-Line-Nozzle (P-L-N) fuel system, the injection pump creates the high pressure necessary for injection and also controls the injection timing.
A diesel engine has higher than specified fuel rail pressure at idle. Technician A says a clogged fuel return could be the cause. Technician B says that a faulty fuel pump could be the cause.
A common rail diesel engine had 2 injectors replaced at another shop. The engine idles rough after the injector replacement. There are no DTC’s. Technician A says to check the injector balance rate volume. Technician B says to check the IQA numbers on the injectors to see if they match the IQA values in the ECM.