A4 Suspension
& Steering
A vehicle pulls to the left at steady highway speed. Tire pressures are equal and correct. Using the readings below, which of these is the cause?
| Angle | Spec | Tolerance | Left front | Right front |
|---|---|---|---|---|
| Caster | +3.5° | ±1.0° | +3.4° | +3.3° |
| Camber | +0.3° | ±0.5° | +0.9° | −0.1° |
| Toe (each wheel) | +0.08° | ±0.05° | +0.07° | +0.08° |
Technician A says a loose tie rod sleeve clamp can allow front toe to change while driving. Technician B says tie rod sleeves are turned to adjust front camber. Who is right?
A jounce bumper (bump stop) is used to:
Which of these is the LEAST likely cause of hard steering at parking-lot speed on a vehicle with hydraulic power assist?
A vehicle tracks straight down a level road, but the steering wheel sits off-center after front toe was adjusted. Which of these should be checked?
With the gauge shutoff valve closed, a power steering pump develops 640 psi. Specification is 1,100 to 1,300 psi. Which of these is the cause?
Technician A says toe should be the last angle adjusted during a wheel alignment. Technician B says a caster or camber adjustment can change the toe reading. Who is right?
Control arm bushing through-bolts should receive their final tightening:
Both front tires show a feathered, sawtooth wear pattern across the tread face. Camber readings are within specification. What is the MOST likely cause?
Which of these is the LEAST likely cause of a rear ride height that measures below specification?
A flexible coupling in the steering shaft is used to:
A vehicle drifts to the left on a level road. Left front caster measures +2.1 degrees, right front measures +3.4 degrees, and specification is +3.0 degrees ±1.0 degree. This indicates:
Technician A says front toe is adjusted at the rack yoke bearing adjuster. Technician B says the rack yoke adjuster is set to control rack-to-pinion lash. Who is right?
One corner of a vehicle continues to bounce two or three times after being pushed down and released. This indicates:
A vehicle measures 1.2 inches below specified ride height at all four corners. Before alignment angles are set, the technician should:
Which of these is the LEAST likely cause of wear on both shoulders of a tire, with the center of the tread wearing normally?
A vehicle leans excessively in turns and a clunk is heard from the front when cornering. Ride height and tire pressures are correct. What is the MOST likely cause?
Technician A says electric power steering assist level may vary with vehicle speed. Technician B says the steering angle sensor may require recalibration after a front toe adjustment. Who is right?
A strut rod (radius arm) is used to:
A customer reports the steering wheel surges and jerks while turning slowly at idle. Power steering fluid level and belt tension are correct. Which of these could be the cause?
A sealed front hub bearing assembly measures 0.008 inch of end play. The maximum allowable is 0.005 inch. The technician should:
Any of these could cause memory steer EXCEPT:
Left front camber is below specification and cannot be brought into range. SAI measures normal on that side and included angle is low. What is the MOST likely cause?
Technician A says a power steering system is bled by holding the steering wheel against each stop for thirty seconds. Technician B says foam in the reservoir means the fluid level is too high. Who is right?
After a tire rotation, the tire pressure monitoring warning lamp is on and stays on. All four tire pressures measure correct. Which of these should be done?
Reading Your Results: A4 Suspension and Steering, Test 1
A score by itself only tells you whether you passed. What follows is how to read the questions you missed on this test. A4 has more genuine adjustability than any other subject on the ASE series, so the recurring lesson here is knowing which angle causes what, and which ones are adjustable at all.
If you missed the alignment angle questions
Three angles do three different jobs, and most wrong answers on this test come from crossing them. Camber is the inward or outward tilt of the wheel viewed from the front, so it wears one edge of the tire and pulls toward the more positive side. Caster is the forward or rearward tilt of the steering axis viewed from the side, so it affects straight-line stability and returnability but does not wear tires, and the vehicle drifts toward the side with less positive caster. Toe is the direction the wheels point relative to each other, and it is the angle that scrubs the tread sideways and produces feathered, sawtooth wear. When a question describes a symptom, name the angle that produces that symptom before you look at the options, because it usually eliminates two of them outright.
If you missed the questions built on a measurement
Three questions here hand you readings against a specification, and each is asking whether you know what that number controls.
If you missed the questions about what is adjustable
Several questions on this test are really asking whether a thing can be adjusted at all. Toe is adjusted at the tie rod sleeves. The rack yoke adjuster sets internal preload between the rack and pinion and has nothing to do with toe. Ride height is not an alignment adjustment, and a vehicle sitting low at all four corners has to be corrected before any angle is set, because the control arms are sitting at the wrong point in their arc. A sealed hub bearing, a modern strut-type camber setup without an adjuster, and a subframe that has shifted all have the same answer: the part or the mounting is repaired, not adjusted. Knowing that list is worth several points on the real exam.
If you missed the component function questions
The three component questions here each solve one problem. A jounce bumper limits suspension travel at full compression so the strut or shock is not driven to its internal stop. A flexible coupling in the steering shaft allows the shaft to run at an angle while isolating road noise and vibration from the wheel. A strut rod, sometimes called a radius arm, locates the lower control arm fore and aft, which is why a collapsed strut rod bushing changes caster on that side and shows up as a pull under braking. On the exam these questions are asking what stops working when that function is lost.