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ASE A4 practice questions

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Question 1Steering Systems

The collapsible section of a steering column is designed primarily to do which of the following?

  1. Reduce the turning radius
  2. Dampen road shock to the steering wheel
  3. Absorb energy in a frontal collision Correct answer.
  4. Increase the steering ratio

Explanation

A collapsible column compresses or separates during a frontal impact so the column does not push into the driver. It works with the column's shear capsules and energy-absorbing design. Steering ratio, turning radius, and road-shock damping are not its purposes.

Question 2Steering Systems

Which component carries steering force from the steering gear to the steering knuckle on a rack-and-pinion system?

  1. Sector shaft
  2. Idler arm
  3. Pitman arm
  4. Tie rod Correct answer.

Explanation

The inner and outer tie rod assembly links the rack to the steering knuckle. The idler arm and pitman arm belong to parallelogram linkage, and the sector shaft is part of the steering gear.

Question 3Steering Systems

A vehicle with a belt-driven hydraulic power steering pump should be serviced with which fluid?

  1. Ethylene glycol engine coolant
  2. The specified power steering fluid Correct answer.
  3. DOT 3 brake fluid from the master cylinder
  4. Engine oil drained from the crankcase

Explanation

Power steering systems require the fluid specified by the manufacturer, which may be a dedicated power steering fluid or a specific automatic transmission fluid. Using the wrong fluid can damage seals and affect steering feel.

Question 4Steering Systems

Which statement correctly describes positive camber?

  1. The top of the wheel tilts outward Correct answer.
  2. The wheel center moves rearward
  3. The steering axis tilts rearward at the top
  4. The top of the wheel tilts inward

Explanation

Camber is the inward or outward tilt of the wheel from vertical. Positive camber tilts the top of the wheel outward, away from the vehicle centerline.

Question 5Steering Systems

Excessive free play at the steering wheel is most commonly caused by which condition?

  1. Worn brake pads
  2. Worn tie rod ends Correct answer.
  3. Misaimed headlamps
  4. Low tire pressure

Explanation

Free play is lost motion between the steering wheel and the road wheels. Worn tie rod ends, worn steering gear parts, or a loose steering shaft coupling are typical causes. Tire pressure, headlamp aim, and brakes do not create steering free play.

Question 6Steering Systems

A squealing noise is heard when turning at low speed on a vehicle with a belt-driven power steering pump. Which is the most likely cause?

  1. Worn strut mount bearings
  2. A slipping pump belt Correct answer.
  3. Excessive positive caster
  4. A seized idler arm bushing

Explanation

When the pump loads up at low speed, a glazed, loose, or contaminated belt can slip and squeal. Checking belt condition and tension is the first diagnostic step.

Question 7Steering Systems

The accordion boot on a rack-and-pinion steering gear serves which purpose?

  1. Hold hydraulic pressure inside the rack
  2. Adjust the toe setting
  3. Keep contaminants out of the rack Correct answer.
  4. Preload the pinion against the rack

Explanation

The boot seals the rack housing where the tie rod exits. It keeps dirt and water away from the rack seal and inner tie rod socket. It carries no hydraulic pressure and makes no adjustment.

Question 8Steering Systems

The turning radius of a vehicle refers to which of the following?

  1. The circle the vehicle traces at full lock Correct answer.
  2. The distance from the steering axis to the tire center
  3. The angle of the front wheels
  4. The diameter of the steering wheel

Explanation

Turning radius, often quoted as a turning circle, describes the size of the path the vehicle follows with the steering at full lock. It depends on wheelbase, track width, and steering angle.

Question 9Steering Systems

A vehicle has a total toe reading of -0.30 degrees, which is toe-out. To bring it to the specified total toe-in of +0.10 degrees, the tie rods should be adjusted so that the front of the tires does which of the following?

  1. Increases camber on both sides
  2. Moves inward Correct answer.
  3. Moves rearward in the wheel wells
  4. Moves outward

Explanation

Total toe is the sum of both wheel toe angles. A negative value means the fronts of the tires point away from each other, so bringing them inward moves the reading toward toe-in.

Question 10Steering Systems

During a power steering pump pressure test, the gauge reads well below specification when the shutoff valve is briefly closed. Which is the most likely cause?

  1. A worn pump or stuck relief valve Correct answer.
  2. A loose steering wheel retaining nut
  3. Excessive positive caster on the front wheels
  4. Air trapped in the system only

Explanation

Closing the valve deadheads the pump, so the gauge should reach the specified maximum pressure. A low reading indicates the pump cannot build pressure, often from worn parts or a relief valve stuck open.

Question 11Steering Systems

In an electric power steering system, the control module uses the steering torque sensor signal to do which of the following?

  1. Adjust the tire pressure monitor threshold
  2. Determine how much assist current to apply Correct answer.
  3. Set the radio volume
  4. Control the brake proportioning valve

Explanation

The torque sensor reports how hard the driver is turning the wheel. The module combines that with vehicle speed and other inputs to command the assist motor current.

Question 12Steering Systems

A recirculating-ball steering gear shows excessive play at the pitman arm. Which adjustment addresses this condition?

  1. Shim the pump mounting bracket
  2. Adjust the sector shaft lash Correct answer.
  3. Replace the idler arm bushing
  4. Adjust the front toe setting

Explanation

Sector shaft lash removes play between the sector gear and the ball nut. Worm bearing preload should be checked first, then the lash screw is adjusted per the service procedure.

Question 13Steering Systems

A vehicle has dark, contaminated power steering fluid and a whining pump. Which is the best first step?

  1. Flush the fluid and check for leaks Correct answer.
  2. Increase the drive belt tension
  3. Replace the rack and pinion assembly
  4. Add brake fluid to the reservoir

Explanation

Contaminated fluid and noise often indicate a fluid or aeration problem, and flushing with the specified fluid is a standard first step. The system should then be inspected for leaks and air entry.

Question 14Steering Systems

Which statement best describes bump steer?

  1. A pull during braking
  2. The wheel returning to center after a turn
  3. A vibration at highway speed
  4. A change in toe as the suspension moves Correct answer.

Explanation

Bump steer is toe change that occurs as the suspension travels. It results from misaligned tie rod and control arm geometry and can make the vehicle wander over uneven roads.

Question 15Steering Systems

After replacing a steering rack on a vehicle equipped with stability control, the technician should perform which action?

  1. Perform a steering angle sensor calibration Correct answer.
  2. Disable the ABS permanently
  3. Top off the system with brake fluid
  4. Replace the yaw rate sensor

Explanation

The stability control system needs to know the straight-ahead steering position. After rack replacement or alignment, the steering angle sensor must be recalibrated with a scan tool.

Question 16Steering Systems

A vehicle has caster readings of +2.0 degrees on the left and +4.0 degrees on the right, and it pulls left. Which statement is correct?

  1. It pulls toward the side with less caster, so it pulls left Correct answer.
  2. It pulls toward the side with more caster, so it pulls right
  3. The pull is caused only by the toe setting
  4. Caster has no effect on directional pull

Explanation

Caster creates a directional force, and the vehicle tends to lead toward the side with less positive caster. With 2.0 degrees on the left and 4.0 on the right, the left side has less caster and the vehicle pulls left.

Question 17Steering Systems

In a parallelogram steering linkage, which component transfers motion from the pitman arm across to the idler arm?

  1. Steering knuckle
  2. Center link Correct answer.
  3. Tie rod end
  4. Sector shaft

Explanation

The center link, also called a drag link, connects the pitman arm to the idler arm. The tie rod ends then carry motion out to the steering knuckles.

Question 18Steering Systems

A front wheel with a worn lower ball joint typically shows which symptom during inspection?

  1. A fluid leak at the rack boot
  2. Hard steering effort only at idle
  3. A vibration felt only above 60 mph
  4. Play between the knuckle and control arm Correct answer.

Explanation

A worn ball joint allows relative movement between the steering knuckle and the control arm. This is checked by prying the joint or observing vertical play with the suspension loaded or unloaded per the manufacturer's procedure.

Question 19Steering Systems

A power steering system is noisy and steering effort is high, and the return hose is found collapsed. Which repair is correct?

  1. Adjust the drive belt tension
  2. Add stop-leak to the reservoir
  3. Replace the power steering pump
  4. Replace the restricted return hose Correct answer.

Explanation

A collapsed return hose restricts fluid flow back to the reservoir, causing aeration, noise, and high effort. Replacing the restricted hose restores normal flow.

Question 20Steering Systems

A rack-and-pinion gear has slight looseness felt over bumps, and play is found at the inner tie rod. Which should be checked first?

  1. Front camber on both sides
  2. Wheel balance and tire radial runout
  3. Inner tie rod play and rack preload Correct answer.
  4. The power steering belt tension

Explanation

Play at the inner tie rod socket and incorrect rack guide preload both produce looseness felt through the steering wheel. Both should be inspected before condemning other components.

Question 21Steering Systems

On a vehicle with independent front suspension, steering axis inclination is out of specification on one side while camber is within specification. Which is the most likely cause?

  1. Worn outer tie rod ends
  2. A bent steering knuckle or strut Correct answer.
  3. An incorrect toe setting
  4. Low tire pressure on one side

Explanation

Steering axis inclination is built into the knuckle and strut geometry, so it is not adjustable. An out-of-spec reading on one side with acceptable camber usually indicates a bent knuckle, strut, or spindle.

Question 22Steering Systems

A power steering pump produces normal maximum deadhead pressure but low flow at idle. Which is the most likely cause?

  1. Excessive positive caster
  2. A worn pump or sticking flow control valve Correct answer.
  3. A loose pitman arm nut
  4. A seized pump drive shaft

Explanation

Maximum pressure and flow are separate pump functions. If pressure is normal but flow is low, the pump's flow control valve or internal clearances are the likely fault.

Question 23Steering Systems

When a vehicle turns, the inner front wheel should do which of the following?

  1. Turn a greater angle than the outer wheel Correct answer.
  2. Turn less than the outer wheel
  3. Turn the same angle as the outer wheel
  4. Remain parallel to the vehicle centerline

Explanation

Ackermann steering geometry causes the inner wheel to follow a tighter radius, so it turns a greater angle than the outer wheel. This reduces tire scrub during turns.

Question 24Steering Systems

What is the primary function of a steering damper on a vehicle with a solid front axle?

  1. Dampen road shock and shimmy at the steering wheel Correct answer.
  2. Center the wheel after a turn
  3. Increase the caster angle
  4. Reduce steering effort at low speed

Explanation

A steering damper is a hydraulic shock absorber mounted in the steering linkage. It controls sudden steering inputs and shimmy caused by road irregularities or large tires.

Question 25Steering Systems

An electric power steering system intermittently loses assist and sets a torque sensor code. Which is the most likely cause?

  1. An incorrect toe setting
  2. Low tire pressure on both front tires
  3. Worn outer tie rod ends
  4. A faulty torque sensor or wiring Correct answer.

Explanation

An intermittent assist loss with a torque sensor code points to a signal problem, such as a failing sensor or a poor connection. The circuit should be tested before replacing the motor or module.

Question 26Steering Systems

Steering wheel free play is being measured on a vehicle equipped with power steering. The measurement should be taken with the front wheels straight ahead and the engine:

  1. running at 2500 rpm
  2. running at idle speed Correct answer.
  3. off with the key removed
  4. off with the front wheels raised off the ground

Explanation

Free play is measured with the tires on the ground, the wheels straight ahead, and the engine idling so the booster is pressurized as it is in normal service. The wheel is turned until the front wheels just begin to move, and that movement is compared with specification.

Question 27Steering Systems

The collapsible section built into a steering column is designed to:

  1. let the driver adjust the column angle
  2. take up wear inside the steering gear
  3. collapse to absorb energy in a frontal impact Correct answer.
  4. damp road shock before it reaches the steering wheel

Explanation

The collapsible section is a safety feature: in a frontal impact the column shortens rather than driving rearward into the driver. It is a one-time energy-absorbing design, not a comfort or wear-compensation component.

Question 28Steering Systems

The threaded adjusting sleeve on a tie rod is used to:

  1. lock the tie rod to the steering knuckle
  2. change tie rod length to set toe Correct answer.
  3. set the preload on the tie rod ball stud
  4. adjust the mesh preload in the steering gear

Explanation

The sleeve joins two threaded tie rod sections, so rotating it changes the overall length and moves the wheel in or out to set toe. The clamp bolts are tightened with the linkage at normal ride height after the adjustment is made.

Question 29Steering Systems

On a hydraulically assisted steering system, a pressure switch threaded into a power steering line is used to:

  1. warn the driver when fluid level is low
  2. disengage the pump drive at highway speed
  3. raise idle speed when steering load is high Correct answer.
  4. limit maximum pressure at full lock

Explanation

The switch senses the pressure rise that occurs when the driver turns the wheel on a stationary or slow-moving vehicle and signals the control module to raise idle speed. This keeps the pump from stalling and preserves assist during parking maneuvers.

Question 30Steering Systems

A vehicle has too little positive caster on the front wheels. Which symptom is most likely?

  1. Wandering and slow return to center Correct answer.
  2. A shimmy that appears only while braking
  3. Rapid wear on the inside edges of both front tires
  4. A pull toward the side with the least positive camber

Explanation

Caster is the steering-axis tilt that makes the front wheels self-align, so too little positive caster reduces straight-line stability and slows the return to center after a turn. Tire wear patterns and braking shimmy are traced to other causes.

Question 31Steering Systems

A vehicle has steering axis inclination of 10 degrees on the left and 13 degrees on the right, with camber within specification on both sides. What does this indicate?

  1. Worn outer tie rod ends on the right side
  2. A bent right steering knuckle or strut Correct answer.
  3. A collapsed front spring on the left side
  4. Excessive total toe-in

Explanation

Included angle is the sum of steering axis inclination and camber. When camber is within specification, a side-to-side difference in SAI and included angle points to a bent knuckle, strut, or spindle on the side with the abnormal reading, because those parts establish the steering axis.

Question 32Steering Systems

The flow control valve in a power steering pump serves to:

  1. bypass fluid when the fluid is cold
  2. relieve pressure when the wheels reach full lock
  3. limit fluid flow as engine speed rises Correct answer.
  4. hold system pressure constant at all speeds

Explanation

The flow control valve regulates the volume of fluid the pump delivers so that flow, and therefore assist, stays nearly constant as engine speed increases. Peak pressure at full lock is handled by a separate relief valve.

Question 33Steering Systems

Compared with a 16:1 steering gear of the same type, a 20:1 steering gear will:

  1. require more effort with fewer turns lock to lock
  2. increase toe-out on turns at full lock
  3. respond more quickly with the same effort
  4. require less effort with more turns lock to lock Correct answer.

Explanation

A numerically higher ratio means the steering wheel must turn farther for a given road wheel angle. That reduces the effort needed at the rim but increases the number of turns lock to lock and slows response.

Question 34Steering Systems

On a speed-sensitive electric power steering system, assist is reduced as vehicle speed increases in order to:

  1. protect the assist motor from overheating
  2. keep the battery from discharging at speed
  3. maintain calibration of the steering angle sensor
  4. improve road feel and stability at highway speed Correct answer.

Explanation

Reducing assist at higher road speed preserves meaningful steering feel and prevents the vehicle from feeling over-assisted or twitchy on the highway. The strategy is about driver feedback and directional stability, not about electrical supply or sensor calibration.

Question 35Steering Systems

Toe-out on turns is designed so that:

  1. the inner wheel steers a sharper angle than the outer Correct answer.
  2. the outer wheel steers a sharper angle than the inner
  3. both front wheels stay parallel through the turn
  4. the rear wheels steer opposite the front wheels

Explanation

Toe-out on turns, or Ackermann geometry, angles the steering arms so the inner wheel follows a tighter radius than the outer wheel. This allows both front tires to roll through the turn without scrubbing sideways.

Question 36Steering Systems

A technician is checking a parallelogram steering linkage for wear. Which method best reveals a worn idler arm bushing?

  1. Measure the distance between the two tie rod ends
  2. Pry the idler arm up and down and measure the movement Correct answer.
  3. Twist the idler arm around the center link axis
  4. Turn the wheel 90 degrees and watch the pitman arm

Explanation

Idler arm wear is checked by loading the arm vertically, usually with a pry bar, and measuring movement at the arm end against specification. Movement beyond specification means the bushing or arm must be replaced.

Question 37Steering Systems

After a power steering pump replacement, the system is refilled. Which procedure best removes trapped air?

  1. Cap the reservoir and drive the vehicle at highway speed
  2. Raise the front wheels and turn the wheel lock to lock at idle Correct answer.
  3. Drain and refill the system without starting the engine
  4. Hold the engine at 2500 rpm and hold the steering at full lock for one minute

Explanation

Air is purged by cycling the steering from lock to lock with the engine idling and the reservoir open, with the front wheels off the ground to reduce load. Fluid level is topped up during the process and rechecked once the air is gone.

Question 38Steering Systems

A vehicle has memory steer: after a turn it continues to pull in the direction of that turn until the driver corrects it. Which is the most likely cause?

  1. Incorrect total toe setting
  2. Excessive positive caster on both sides
  3. Worn inner tie rod sockets
  4. A binding strut bearing or upper mount Correct answer.

Explanation

Memory steer means something in the steering or strut mount is binding and preventing the wheels from returning freely once the turn is completed. A binding strut bearing or upper mount is the classic cause of this complaint.

Question 39Steering Systems

A recirculating-ball steering gear is adjusted with excessive worm bearing preload. Which symptom would this produce?

  1. High steering effort and poor return to center Correct answer.
  2. A vibration felt only at highway speed
  3. Uneven tire wear across both front tires
  4. Loose, wandering steering with excess free play at the wheel

Explanation

Worm bearing preload is set at the input shaft, and too much preload makes the gear bind, so effort is high and the wheel will not return to center freely. The tightness remains even with the pitman arm disconnected, which separates it from binding in the linkage.

Question 40Steering Systems

An electric power steering system intermittently drops assist and sets a torque sensor code. Which is the most likely cause?

  1. Low tire pressure on one front tire
  2. High resistance in the torque sensor circuit Correct answer.
  3. A worn inner tie rod socket
  4. Excessive positive caster

Explanation

The control module needs a continuous, accurate torque sensor signal to command assist, so a poor connection, chafed wire, or high resistance in that circuit can cause intermittent assist loss and a stored torque sensor code. Mechanical and alignment conditions do not set this code.

Question 41Suspension Systems

What is the primary function of a shock absorber or strut damper in a suspension system?

  1. Control spring oscillation by converting motion to heat Correct answer.
  2. Maintain alignment angles as the suspension moves
  3. Keep the tire flat on the road during cornering
  4. Support vehicle weight and establish ride height

Explanation

A damper converts the kinetic energy of suspension movement into heat through hydraulic fluid forced through valving, which limits how many times and how far the springs oscillate. It does not carry vehicle weight or set ride height; the springs do that.

Question 42Suspension Systems

A vehicle sits noticeably lower at the left rear than at the right rear, and the left rear coil spring is visibly collapsed and weaker than the right. Which repair is correct?

  1. Replace the left rear coil spring Correct answer.
  2. Replace the rear stabilizer bar links
  3. Replace the left rear lower control arm
  4. Replace the left rear shock absorber

Explanation

Ride height at a corner is set by the spring, so a collapsed spring that lets that corner sag must be replaced. A weak damper affects ride control but will not hold a corner of the vehicle down at rest.

Question 43Suspension Systems

What is the primary function of a ball joint in a suspension system?

  1. Attach the wheel hub to the axle shaft
  2. Dampen road vibration before it reaches the vehicle body
  3. Limit suspension travel at the end of the rebound stroke
  4. Act as a pivot between the control arm and knuckle Correct answer.

Explanation

A ball joint is a spherical pivot that lets the steering knuckle move through jounce, rebound, and steering while holding the control arm to the knuckle. The stud and socket design allows motion in multiple planes, which a simple bushing or clevis cannot provide.

Question 44Suspension Systems

Which observation during a suspension inspection most directly points to a worn damper?

  1. The body keeps bouncing after a push-down test Correct answer.
  2. The steering wheel shimmies at parking lot speeds
  3. The tire tread shows feathered edges across the face
  4. The vehicle pulls to one side only during braking

Explanation

A push-down test that produces more than one or two rebound cycles shows the damper is not controlling spring energy. Fluid leakage on the damper body and cupped tire wear support this diagnosis.

Question 45Suspension Systems

What is the purpose of a stabilizer bar in a suspension system?

  1. Vary caster as the suspension compresses
  2. Reduce body roll during cornering Correct answer.
  3. Absorb engine torque reaction during acceleration
  4. Increase load capacity when the vehicle is loaded

Explanation

A stabilizer bar links the two sides of a suspension through torsion; when one side compresses, the bar twists and resists further roll. It also affects the balance of grip between the front and rear axles.

Question 46Suspension Systems

Which statement about a MacPherson strut suspension is correct?

  1. It requires upper and lower control arms to locate the knuckle
  2. It cannot be removed without dropping the steering rack
  3. It combines the spring and damper in one locating unit Correct answer.
  4. It is used only on rear suspensions with a solid axle

Explanation

In a MacPherson design, the strut assembly carries the coil spring and damper together and its upper mount also serves as an attachment point that positions the knuckle. Only a lower control arm is used, which is what makes the layout compact.

Question 47Suspension Systems

A toe setting on an alignment machine is expressed as the difference between which two measurements?

  1. The distance between the tires measured at front and rear Correct answer.
  2. The tilt of the wheel from vertical viewed from the front
  3. The forward or rearward tilt of the steering axis
  4. The angle between the steering axis and the wheel centerline

Explanation

Toe compares the track dimension measured across the front of the tires with the dimension across the rear of the tires; the difference is expressed in degrees or as a linear distance. Toe-in means the front dimension is smaller than the rear dimension.

Question 48Suspension Systems

What does turning the adjusting bolt on a torsion bar suspension change?

  1. The spring rate of the torsion bar
  2. The ride height of the vehicle Correct answer.
  3. The camber angle at that wheel
  4. The rebound valving of the shock absorber

Explanation

The adjusting bolt rotates the anchor of the torsion bar, changing how much the bar is pre-twisted and therefore how much load it applies to the control arm. Changing that preload raises or lowers the corner of the vehicle.

Question 49Suspension Systems

Adding positive caster to a front suspension generally produces which effect?

  1. A change in the thrust angle of the rear axle
  2. Better straight-ahead stability with higher steering effort Correct answer.
  3. Reduced steering effort with noticeably slower return to center
  4. Accelerated wear along the inner edge of both front tires

Explanation

Positive caster places the tire contact patch behind the steering axis, so the wheel tends to trail and self-center, improving high-speed stability. The trade-off is heavier steering effort and more steering-axis load.

Question 50Suspension Systems

A front tire shows accelerated wear on its outer shoulder while the inner shoulder looks normal. Which alignment condition is most likely responsible?

  1. Excessive negative caster
  2. Excessive positive camber Correct answer.
  3. Excessive toe-out on the front axle
  4. Excessive rear thrust angle

Explanation

Positive camber tilts the top of the wheel outward, which loads the outer shoulder and wears it faster than the rest of the tread. Toe wear typically produces a feathered pattern across the whole tread face rather than shoulder-specific wear.