How to judge the quality of a car

Question 1: How to judge the performance of a car? Motivation is the part that everyone pays great attention to. In fact, when Chinese people buy a car, the first thing they look at is the appearance, and the second thing they ask about is the engine. Fortunately, you can judge the former by looking at it, but the latter is invisible to the naked eye, and you may not be able to judge it even if you drive it in person. So how do you judge the quality of a car's power system? Let’s talk about some of these methods.

Specifications

Before getting in touch with a car, we often look at its technical specifications. Technical specifications about the power system include many items, such as the displacement, horsepower and torque figures, how many cylinders, how many valves, dual camshafts or single camshafts, whether the cylinder block is made of aluminum or cast iron, and whether there are any advanced technologies, etc. wait. These things are all worth looking at. In theory, the higher the specifications, it means that the design year of the power system is newer, and the potential may be better. But you should never judge the quality of an engine by its specifications alone. What we value more is the actual performance of the engine.

The most obvious thing about the actual performance of the engine - and what each of us has the ability to judge - is a characteristic called NVH. NVH refers to Noise, Vibration and Harshness. Noise and vibration are easy to understand. When you sit in a car, first when it is idling, as long as you pay a little careful attention, you can feel whether the car is quiet or noisy, smooth or trembling; then start the car and start driving at various speeds. Speed ??range, for example, for a manual transmission car, you can accelerate slowly in 1st gear, from 1,000 rpm, 2,000 rpm, 3,000 rpm... all the way to 6,7,000 rpm in the engine's red zone. During this period, pay attention to the noise and noise of the engine. Changes in vibration. Generally speaking, the higher the engine speed, the higher the internal operation requirements. At this time, the vibration may increase, and the sound may also change with the speed. All you have to do is to judge whether the sound is pleasant or noisy. If there is any disturbance, whether the vibration amplitude of the engine is within the acceptable range for you.

A good engine should vibrate very little under all circumstances, and it should not cause resonance in any components in the car, even at the highest speed. In terms of sound, some engines are very quiet from low to high speed, which is of course a very good engine; there are also some engines that have a more noticeable sound, but it may be a nicer sound. In some sports cars, there is often a sound. Deliberately create some sounds. As long as the sound is smooth and pure, it means that the engine's craftsmanship is relatively refined. In short, the subtler the engine vibration, the better; and the purer the sound, the better.

The NVH performance of the power system can be felt and judged by yourself as long as you pay attention. It does not require any special professional skills. Therefore, this is a method that is most suitable for our current national conditions to judge the quality of the engine. Because the current problem with many domestic car engines is not the technical content, but the manufacturing process. NVH performance can best reflect the manufacturing process of an engine, and the process often represents its performance and durability.

Engine Character

When it comes to measuring power, the most direct indicators are the two data of power and torque. But I don’t want to explain these two concepts too much from physics here. Simply put, power indicates how fast the engine is, and torque indicates how powerful it is. However, these two indicators are actually indicators that reflect the design and manufacturing level of the engine, and what we value more is the actual characteristics of an engine. In terms of power output, an engine has a "character", and this character is represented by a power characteristic curve in engine technology.

The data reflects the strength of an engine, and the characteristic curve reflects its character. When we drive or test drive, the most important thing is not to look at its horsepower and torque figures, but to fully understand the character of the engine, and then operate it in a method that best matches its character to maximize its performance.

There is no absolute criterion for judging the quality of a character. It mainly depends on whether it is applicable or whether you like it.

In the past, car engines paid more attention to the comparison of output figures. Therefore, the power of the front section was often insufficient, and sufficient power could only emerge at higher speeds. However, the current mainstream international standard is a peaceful and balanced character, which is designed to function well in various environmental conditions. Both have balanced power performance, and it is easier for users to adapt.

However, there are still different standards for this character for different types of cars. For example, for people who do modifications and racing, they need to pursue a surging sense of *** in the final stage. How about the character in the early stage? It often has nothing to do with it; but for heavy-duty trucks, they need a strong front end, and even weak stamina is acceptable. Therefore, only by analyzing the specific uses of different models can we determine...gt;gt ;

Question 2: How to judge the quality of a car? Pay attention to a few parameters, appearance, engine, instrument panel, tires, and you will basically avoid being cheated

Question 3: How to judge the quality of a car. Pay attention to a few parameters, appearance, engine, and instrumentation. If you don’t worry about the discs and tires, you will basically not be cheated

Question 4: How to identify the quality of the car. You must read it when choosing a car. Don’t be fooled by profiteers. The first step: look at the chassis and battery of the car

Everyone has said, what’s so good about the new car? Wrong, new cars also leak oil! I lay down and looked to see if there were any oil spots on the ground and whether there was any oil stain on the chassis. There is not much to look at in a new car battery, just check whether the connector is corroded and whether the small window is green. Note that the battery connector is usually loose and must be tightened before driving away.

Step 2: Pull out the oil dipstick to check the oil color.

Some people say again, aren’t they all 0 kilometers? Of course, "0 kilometers" does not mean that the number displayed on the odometer is absolutely "0". It is generally believed that anything with an odometer below 60 kilometers can be considered "zero kilometers." But the dealer is out of order. Some cars have run many kilometers, but the odometer does not pick up, and it is still more than ten kilometers, and it is pretended to be 0 kilometers! When checking, turn off the engine after driving the car for three minutes, pull out the oil dipstick and wipe it with a paper towel to eliminate the black spots. Now JS also knows this, so when I asked for inspection yesterday, the dealer immediately pointed out my intention. They were already prepared, so it was useless to look at it.

Step 3: Listen carefully to the sound of the engine

I have developed a habit of driving. Whenever I drive a car for the first time, I like to open the front cover and hold the end of a screwdriver against the engine. Put the other end against your ear to listen to the sound, which is a way to gain experience. This was a big help when choosing a car, almost half of the cars were eliminated and only two were left. (Don’t laugh! It’s better to be careful when choosing something as expensive as a car. The more serious you are, the less likely the dealer will be sloppy with you!) Here’s a detailed explanation so that you can hear whether there is any noise inside the engine, such as ring noise. , cylinder knocking sound, valve beeping sound, etc. A good engine has only one "purr" sound and no other noises. However, this method relies on the accumulation of experience that is usually carried out consciously. It cannot be explained in a sentence or two. In short, it is better to listen to more cars. A wordy sentence: When someone can help, ask them to step on the accelerator and increase the engine speed while you listen to the sound. Then ask him to use some rag to block the exhaust port. If the engine sound becomes significantly duller and stalls in a few seconds, it’s a good car! Otherwise, there is an air leak somewhere. (I blocked it myself at that time, and the dealer looked very ugly! Hehe.)

Step 4: Start the engine, and pay attention to the change of the tachometer pointer during cold start

Normal Under normal circumstances, the pointer should reach about 1600 rpm, and then slide down to 800 rpm in a normal smooth arc (in outdoor vehicle inspection in the north in winter, it drops back to about 1200 rpm, and gradually returns to 800 rpm after starting the hot car for a few minutes). Then observe whether various instruments and alarm devices are working normally. When the water temperature and oil pressure are normal, check the sound and response of the engine. First, listen to the idling sound. It should be smooth and continuous, and there should be no metal knocks. noise and other abnormal noises.

Get off the car and observe whether the exhaust pipe smoke is normal. Put your hand to the exhaust port to feel whether the exhaust is continuous. Normally, the palm of your hand should be a little moist but should not smell of oil, and then listen. Check whether the engine sound is continuous during slow refueling and whether there is any abnormal noise. Finally, listen to the sound of rapid acceleration and whether the engine's response to the throttle is accurate and rapid. Also pay attention to whether the engine's response during slow refueling and fast refueling is clean. If there is any lag, Or there is a high-speed whistle, there should be something wrong. Turn off the accelerator (relax the accelerator pedal) and see if the idle speed is stable. When standing still, will there be a different roar when the engine speed reaches 3500 rpm?

Step 5: Check the workmanship

It depends on the connection of each thread, whether there is any shaking, etc. You can see this for yourself, so I won’t say more.

Step 6: Look at the appearance of the entire car.

Some people will say, are you only looking at the appearance now? Of course, this is not about choosing a second-hand car. If there are scratches on the appearance, the car will not be parked there waiting for you to pick it up. The dealer will deal with it early in the morning. What I want you to look at is whether the gaps in the door are even. In addition, when looking at the appearance, you should also pay attention to whether the glass is original and whether the bottom of the glass is marked, so as not to end up with a car that has been in an accident (this has happened before). In addition, I think the dealer can basically handle small scratches seamlessly and cannot be seen without looking very carefully. However, if the tire is damaged in an accident, it cannot be repaired as long as the dealer does not replace it, so I will focus on As for the tires, sure enough, a car in the showroom that the dealer strongly recommended to me had a puncture the size of a peanut in the right front tire. The car was immediately dismissed and the tires of the car were probably replaced today.

Step 7: Check the cockpit

This is the time when you enter the cockpit. Dealers say that if you can’t wait to enter the cockpit to pick a car as soon as you see it, you will know it. Newbie! What I'm most afraid of is the one who hangs around the machine for a long time without entering the cockpit. There’s nothing to say here. Look at the manual and check whether the various buttons and switches are...gt;gt;

Question 5: How to judge the performance of a car. Some people say that it depends on its horsepower. But many experts say it depends on the torque.

Many people usually don’t understand the issue of horsepower and torque. If we explain it in professional terms, more people may fall into confusion and never understand it. We will use simple Let’s take a look at this problem.

In fact, the higher the horsepower, the higher the maximum speed (Max Speed); the higher the torque, the stronger the instant acceleration. To put it simply, it will be faster when starting or suddenly accelerating.

To give a simple example, the torque output of general commercial vehicles is quite large, so these vehicles have strong instantaneous acceleration in the low speed range (about 2500rpm to 4000rpm). But the weakness is that the horsepower output is relatively small.

Therefore, we see that some trucks may be as good as cars when starting at a red light, but on high-speed kilometers, even if the top speed is not limited, it is difficult for them to reach a speed of 120 kilometers per hour.

Let’s take another example of a car. Compare a 1.6-liter Civic with 115 horsepower and a 2.0-liter Golf with the same 115 horsepower. The top speeds of the two cars should not be far apart, but the Golf's maximum torque is 16.9kgm/3200rpm, while the Civic's maximum torque is 14.6kgm/5500rpm.

In the low-speed range, the Golf performs better than the Civic. When accelerating from 0 to 100 kilometers per hour, the Golf definitely has an advantage. But after the speed exceeds 100 kilometers per hour, the performance of the two cars depends on whose gear ratio is better matched.

Question 6: How to judge the performance of a car? This question is very game-like.

Performance should be judged based on needs

If you like speed, look at acceleration results

If you like comfort, look at ride performance and body materials

If you like off-roading, look at the four-wheel drive system and ride height

If you like fuel economy, look at the variable box, engine displacement, tire model and specifications

There is no end to the car, choose the one that suits you

Question 7: How to evaluate the quality of a car is a very complex question. To put it simply, the key depends on your preferences: Generally, evaluation is based on body safety, interior decoration, driving comfort, acceleration performance, and maintenance costs.

Question 8: How to judge the quality of a bicycle? Liz’s question is very sharp. In fact, you can look at a bicycle from many aspects: 1. Brand (Spike, Giant...) 2. Weight. For road racing, an aluminum alloy frame is naturally better, but for mountain riding it’s a different story (if you want good stability, choose a steel frame). 3 Tires. Take the front wheel as an example: Lift the front of the car and see if the tires are in a straight line when rotating. This is purely to see if the tires are regular. 4. Speed ??change. It is recommended to use a thumb shift transmission. The shifter is very twisty, so it is not convenient to change gears when riding. 5 chainrings. Usually it’s “three in the front and six in the back” (three teeth in the front, six in the back), this... I feel the more the better, for example, there are many tips for “three in the front and eight in the back”. You can find a pure hand model on the China Bicycle Network. , hope to adopt it

Question 9: How to judge the quality of a second-hand car. Recently, many people are asking how to choose a second-hand car that suits them, or which car is better at preserving its value. You can see More and more people are paying attention to used cars. So let’s talk about the issues that should be paid attention to when buying a second-hand car:

First, before buying a second-hand car, you must clearly understand the usage time, that is to say, whether you are buying this second-hand car for transitional practice, or for Long term holding. The length of use will determine the direction in which you choose a car. Generally speaking, people who are transitioning to practice in the short term should choose a model with a higher value retention rate, so that the loss will be smaller when changing the car again. You can refer to, for example, Lobo, Jetta, Bora, Accord, Magotan, etc. These models all have higher value retention rates in the same class. There is a rule that models with large volumes in the local market tend to retain their value. The biggest advantage of such models is that they are easy to maintain, have a wide supply of spare parts and are cheap. If the second-hand car purchased by the consumer is to be held for a long time, the choice of car model will be much more relaxed. Except for some extremely rare models, it doesn't matter if you bring some personal preference when the price is reasonable.

Secondly, we must pay attention to the car condition and procedures, which is also the most important link in the second-hand car buying and selling. Some people say that they are not in the industry, how can they know the condition of the car and whether the procedures are complete? Indeed, there are indeed many "tricks" in second-hand car transactions that most people cannot detect. Nowadays, second-hand car transactions are gradually being standardized. In this case, it is recommended to go to some larger regular second-hand car brokerage companies to purchase second-hand cars. The price may not be the cheapest, but at least the condition of the car and the procedures are guaranteed to be no problem. of.

When buying a second-hand car, "look, hear and ask"

"Look" at the appearance of the car body, the interior of the car, the trunk, etc. When buying a second-hand car, remember not to rely on the first impression that the model is fashionable or superficial. If there are no scratches, you will have the urge to buy. You must carefully observe the appearance of the car. You can observe it carefully from the outside to the inside. When inspecting the car interior, you should check the instrument panel one by one to see if the function key switches and indicator lights of the steering wheel are intact. A good steering wheel should not have any gaps up and down when shaken by hand, and the left and right swings should not be too large. Also pay attention to whether the window glass can be raised and lowered freely and whether the sealing is good. The seat surface should be clean and free of damage, and it should slide forward and back smoothly without obstruction. When checking the trunk, open the cover. If you find traces of sheet metal on the edge, it means that the car has been rear-ended. At this time, observe the light reflection and color difference of the rear fender (trunk side panel).

"Smell" the engine

Check the appearance of the engine, identify traces of oil leakage and water leakage, start the engine, and observe the color of the exhaust gas. If it is translucent light gray, the engine is in good condition. , if the exhaust gas is black, it means the engine is not adjusted properly. You can also identify it by the sound. A machine with a crisp sound and a strong sense of rhythm is generally a good machine, but some models are designed to be relatively deep. In short, the engine must be clean and tidy, with no oil leakage or leakage, and the sound rhythm must not be chaotic.

"Ask" about the factory date

Because our country has clear regulations on the service life of vehicles, generally small cars should not exceed 15 years. Therefore, when buying a second-hand car, be sure to check the factory date of the vehicle to avoid buying back a vehicle that is about to be scrapped. The vehicle's factory date can generally be found out through the vehicle's nameplate or the original user's registration record. The most accurate method is to look up the technical information of the vehicle model.

"Cut" road test inspection

Start off and check whether the clutch engagement is smooth and whether there is any vibration or abnormal noise. Start on the spot and accelerate, step on the accelerator to see if the speed increase is sensitive, and check if the speed increase is strong on the slope. If the speed increase is slow and there is no force when going uphill, it means that the engine power is insufficient. The transmission system can be inspected by coasting in neutral while driving, and the quality of the transmission performance can be judged based on the length of the coasting distance.

In addition, we also remind all car owners that the contract is very important. When buying or selling a second-hand car, you must have a complete car purchase contract and truthfully provide the real situation, including the mileage, car condition, etc., and implement it in written form. . A complete car purchase contract is more important than the experience of experts.

Identify the quality of second-hand cars

In the process of selecting a second-hand car, the frame is a very important inspection part. Don’t take it lightly. If you have difficulty grasping it, find a A friend who knows about maintenance will accompany you to help you check. Consumers always worry about whether there will be a major accident when choosing a second-hand car. Yes, the extent of the accident is directly related to the final transaction price. When choosing a second-hand car, in addition to understanding the quality of key components such as the engine, brakes, transmission, transmission, and electrical equipment, it is also very important to understand the vehicle's previous accidents. And checking the frame is a good way to determine whether the car has been involved in a collision. Look at the watch...gt;gt;

Question 10: How to measure whether a car is good or bad? 1. Cost-effectiveness! Of course, spending the same money will make you feel comfortable if the performance is good.

2. Looking at the engine, generally turbocharging responds faster than naturally aspirating and is more powerful, but it is not necessarily better than turbocharging. Because turbocharged engines are relatively expensive to maintain. (Turbocharged German cars have better engines, especially Volkswagen and Audi)

3. Compare from 0 to 100km/h, and the data can be obtained during test drives or evaluations. The shorter the time it takes to accelerate from standstill to 100km/h, the better the performance.

4. Compare from the exhaust volume. Those with larger displacement should start faster.

5. Also compare from the after-sales service. The better the after-sales service, the more comfortable it is to use the car. By the way, Toyota's after-sales service is famous for being considerate and comfortable.

6. From the fuel consumption ratio (if you are using a private car). A car with low fuel consumption will not make you nervous when driving, and you should always pay attention to the price of fuel.

7. Space. The bigger the space, the more comfortable the ride, and the more respect you can have with friends.

9. Interior, the texture of the interior also determines your face.

10. Brand awareness.

...

The above are arranged in order, the higher the priority, the more important. In fact, there are many more, but these ten points are enough to evaluate a car. "Good or bad".

In fact, a car is not good or bad. For example, if you are interested in a car with low fuel consumption, then the Yaris is better than the A4L...right? Whether this is good or bad depends on what you focus on~

I would like to add that if you choose my answer, there is no need to add points. I will not give you any points. I am also a car fan!

I wish you choose a good car as soon as possible! ! !