What causes the car to deviate during Subject Three driving test?

[Correia]

The main reasons for a car deviating during the Subject Three driving test are threefold: 1. Driving tire pressure: Inconsistent driving tire pressure causes uneven wear between the driving wheels and the ground, leading to deviation. 2. Suspension system failure: Issues such as suspension damage, deformation, or misalignment can cause the car to deviate. 3. Unequal wheelbase on both sides: When the car is moving, it will tend to deviate towards the side with the shorter wheelbase. Below is relevant information: 1. Driving phenomenon: Car deviation refers to the tendency of a car to automatically steer left or right when driving at a constant speed on a flat, straight, dry, and clean cement or asphalt road after releasing the steering wheel, resulting in the centerline of the front and rear axles not aligning with the centerline of the driving trajectory. 2. Influencing factors: Due to factors such as car structural design and manufacturing precision, a car that does not deviate at all does not exist. Typically, if a car deviates more than 5 meters when driving 1000 meters on a flat straight road, it can be considered as deviation.

[KendraLee]

Vehicle deviation is quite common in the Subject 3 driving test, mainly due to novice drivers' lack of proficiency. I often see students gripping the steering wheel too tightly or making overly large steering movements, which can lead to loss of control and veering to one side when nervous. Hold the steering wheel lightly, using your thumbs to guide it gently, rather than gripping it tightly. Keep your eyes fixed on a distant point ahead on the road, and avoid distractions like constantly checking the rearview mirror or roadside markings. Vehicle-related issues such as uneven tire pressure or slight misalignment in wheel alignment can also contribute, but test vehicles are usually well-maintained, so these are rarely the root cause. When practicing straight-line driving, focus on making smooth, minor adjustments to the steering—never jerk the wheel suddenly. If you start to deviate during the test, don’t panic; correct it with small, timely adjustments instead of trying to fix it all at once. It’s advisable to do more simulated practice before the test to improve your sense of direction and confidence, which will help you stay steady during the actual exam.

[AutumnMarie]

When I was taking the driving test for Subject 3, the car kept veering off course badly, and I felt extremely nervous, constantly thinking I would fail. The main reasons were improper steering wheel handling, applying too much uneven force with my hands causing the direction to skew, and the seat not being adjusted properly, leading to an off-center sitting posture and unstable balance. The instructor reminded me to relax my shoulders, focus my vision on a target about a hundred meters ahead, and not fixate on the ground markings; when turning the steering wheel, make smooth and slight corrections. Vehicle issues like tire problems or uneven road surfaces might exacerbate the veering, but the main issue lies in driving habits. After more practice, I got the hang of it: maintain a steady speed, avoid sudden acceleration or braking, and make gentle, gradual steering adjustments. Exam mentality is also crucial—don’t fear mistakes, calmly reset if the car veers, as success in the test relies on composure and proficiency.

[AlexisLee]

If the car keeps veering off course during the Subject 3 test, from an automotive perspective, first check if the tire pressure is consistent on both sides. A significant pressure difference can cause unbalanced traction, pulling the car to one side. Next, inaccurate four-wheel alignment parameters, such as incorrect wheel camber, can make the car prone to tilting or veering. Worn or faulty suspension components can also affect straight-line stability. Beginners who make abrupt steering inputs or sharp turns during practice may exacerbate these issues. It's advisable to briefly inspect tire conditions before driving, handle the steering wheel gently during the test, and maintain consistent speed to minimize additional resistance. Regular vehicle maintenance can prevent mechanical issues, but most students' veering problems stem from insufficient driving skills—practice makes perfect.