Introduce a new car, so it is foolproof to test the quality of the engine

You need to check clearly when you bring up a new car.
If there is a quality problem, you can negotiate with the 4s shop to request a new car
.

So how can I find the problem when I mention the car?

1.
Odometer reading: Generally, the total mileage should be less than 20km
.

2.
Check the production date and shipping date.
The scheduled date of delivery of the car should be within one month; it is recommended not to mention the current car with the delivery date of more than three months, so as not to mention the show car and test drive
.

3.
Look at the appearance: slowly go around the car to see if there are obvious paint injuries on the car body.
Observe that the car body gaps should be even.
It is important to check whether there are scratches caused by the transportation process
.

4.
Look at the interior: the interior should be clean, especially the dirty parts, such as the inner handle, around the interior lights and the seat
.

5.
Look at the door: the qualified door switch is evenly applied and has no abnormal noise
.

6.
Look at the ground: the ground under the vehicle after a period of operation, the normal situation is that there should be no water or oil leakage in other parts except for the water drop on the exhaust pipe
.

7.
Look at the tires: a normal new car tire should have no damage to the sidewall, especially the front tire wall
.

8.
Light system inspection: turn on various light groups, check whether the high beam, low beam, fog lamp, double flashing light, turn signal, etc.
are normal, check the brightness of the left and right lights, and whether the flashing frequency is the same
.

9.
Electrical system inspection
.

1) First spray some glass water to check whether the wiper has blind spots or abnormal noise
.

2) Each car window should be raised and lowered smoothly without abnormal noise.
Check the anti-pinch function of the one-button lifting
.

3) Audio Check whether the audio sources such as cd, radio, aux interface work normally, adjust the volume, and adjust the various sound effects.
Finally, turn the sound up and listen to whether the speaker has broken sound
.

4) When checking the air conditioner and heating air, mainly ensure that the rattling sound of the air conditioner and heating working fan vibration, especially when the cold air is turned on, will affect the engine idling speed
.

5) Other electrical systems, such as electric rearview mirrors, should also be checked to ensure that they can work normally
.

For these matters, car owners need to have enough patience
.

But the inspection of the engine is the top priority
.

1) Cold start the engine and start it after igniting it once or twice
.

2) The engine speed should be stable when the car is warming up
.
Press the palm of your hand firmly on the steering wheel or the side panel of the gear handle, and the vibration should be stable, uniform, and no irregular vibration; the engine noise should be basically inaudible in the car
.

3) Turn on the air conditioner when the car is hot and check the effect on idling speed and jitter.
Under normal circumstances, it is normal for the idling speed or jitter to increase slightly after turning on the air conditioner
.
However, some cars have been adjusted to a low idle speed and become tractors as soon as the air conditioner is turned on
.

4) Tap the throttle, the response is responsive
.
When the speed increases, the jitter should become smaller or unchanged
.
It should be noted that if the jitter becomes larger, it may indicate that there may be problems such as misalignment of the half axis, sideways of the flywheel, and too low resonance zone
.

This test is entirely based on personal feelings.
It is recommended that you open the YouQuan drive for synchronous test during the vehicle inspection process
.
The test is very simple.
After downloading YouQuanDrive, put the phone on the side of the gear, start the engine, and press the start test for 3 minutes to see the test result
.
You can clearly see the data changes, as long as the mobile phone is enough, 0 peripherals, 0 cost
.

The test chart of the new car is like this:

Of course, the jitter of different car systems is different.
The following are the different reference ranges for the jitter of the new car:

In fact, whether the car is good or not, just look at the two lines, the speed line and the jitter line
.
If the vibration of the two lines is in a straight line, and the vibration is within the above-mentioned reference range, it can be basically determined that the quality of the car is good, with low vibration and low noise
.
Essentially, the root cause of noise is also caused by vibration
.

Cars with unstable idling speed and excessive jitter have quality problems when they leave the factory.
Even if the 4S promises a warranty, it will only get worse with repairs, and there are few improvements
.

In the middle and right pictures below, the quasi-new car that has not arrived at the first guarantee has large noise and jitter, and there is no improvement after repeated claims for repairs in 4S
.

Of course, if you have no idea, you can find a few cars of the same series to do a test comparison to see what the characteristics of the normal new car test results are, and effectively avoid the winning car when picking up the car
.
Of course, remember that when you pick up the car, hlod stays excited and checks calmly
.