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what does it mean when your speedometer jumps
Reasons for the car speedometer jumping:
1. It is caused by the failure of the vehicle speed sensor.
Solution: go to the 4S store for maintenance as soon as possible.
2. When the air, gasoline vapor and combustion exhaust gas that should not enter enter the intake manifold, the mixture will be too rich or too lean, causing abnormal engine combustion.
Solution: go to the 4S store for maintenance as soon as possible.
3.Defective flexible shaft, damaged instrument or poor installation of flexible shaft lock nut.
Solution: Replace the flexible shaft and meter or change the installation method of the flexible shaft nut.
4. There is a fault in the charging line, which may be caused by generator fault, battery voltage sensor fault, loose battery pile head, etc.
Solution: go to the 4S store for maintenance as soon as possible.
5. The throttle valve has a fault. The fault of the throttle valve may be the fault of the throttle position sensor or the fault of the throttle control motor.
Solution: go to the 4S store for maintenance as soon as possible.
It also maybe the charging line is defective:
Charger failure may be caused by generator failure, battery pack voltage sensor failure and loose battery pack.The generator needs to be recharged when the car is running. When the battery cannot be charged or fully charged, the engine ECU will increase the engine speed, let the generator charge the battery, and make the tachometer jump up and down during driving.When stepping on the accelerator, if the speed is up and down, first check whether the fault light in the instrument panel is on. If it is not on, it means that there is no problem with the sensor, which may be due to insufficient power supply voltage, air leakage in the intake manifold, motor idling, etc. If you need to check the problems of the car yourself, you can first open the hood of the car and remove the steam filter of the throttle valve; Then start the car to block the throttle valve. If the car does not stop after blocking, check the nearby pipes to see if there is air suction. If there is air leakage, it needs to be replaced.
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