tachometer jumps all over

• 2022-03-11

The engine tachometer is the direct feedback mechanism of the engine speed. The tachometer automatically jumps randomly. If the problem of the tachometer itself is eliminated, it means that the engine speed is unstable. The unstable engine speed may be caused by excessive carbon deposition in the throttle valve, idle motor, intake port, intake valve, combustion chamber and fuel injection nozzle.

Still, we can clean the energy injection snoot and input manifold first, If the engine tachometer jumps all over. Also check and clean the carbon deposit inside the throttle stopcock and combustion chamber. Because during cold launch, carbon deposit will adsorb a certain admixture, which will lead to too thin admixture and poor atomization of admixture during launch-up, performing in uneven combustion state of theengine.However, the admixture is too rich during incipiency, which will also make it delicate to start, If there's a problem with the carbon barrel or carbon barrel solenoid stopcock. The operation of spark entrapments can be checked. Due to the failure of clutch switch or other detectors, because the machine is controlled by ECU, the computer will continuously collect the signals of colorful detectors and control the energy injection quantum of the machine during gear shift, refueling and canvas collection. Formerly there's a problem, the computer program will be disordered and the rotating speed will be unstable. The sound of oil is louder, which may be due to the power loss of the battery or the low power generation of the generator, resulting in the low power and slow speed of the fan at idle speed. When refueling, when the power generation comes up, the fan speed will speed up, so the noise will be loud. It is recommended that you go to the 4S store for inspection and troubleshooting as soon as possible.

If the idle speed of the car is unstable, there will be some hazards: if the idle speed of the car is too high, check whether the intake manifold is loose or leaking, which will greatly increase the fuel consumption and increase the carbon deposition of the engine. If the idle speed of the car is too low, there will be potential safety hazards of flameout at any time during driving. When the car idles at high and low speed, the spark plug or high-pressure bag may not work, resulting in the engine piston not working and causing severe shaking.