What is the phenomenon after the engine air flowmeter is damaged?

If the air flowmeter is broken, there will be unstable idle speed, weak refueling and black smoke, and it may not work (if you are in doubt, you can unplug the air flowmeter, and if it works, it means that the flowmeter has been damaged).

The common faults of air flowmeter are short circuit, open circuit or abnormal intake signal, which will make the computer unable to measure the intake air entering the engine correctly, thus unable to control the fuel injection normally, resulting in the mixture being too rich or too thin, which will make the engine run abnormally.

Because the difference between the intake air volume when the engine idling throttle is fully closed and the intake air volume when the automobile accelerating throttle is open can reach more than 40 times, and the maximum intake air flow can reach more than 80m/s, the air flowmeter should be able to accurately measure the intake air volume within these changing ranges, and the air flow should not be hindered during the measurement, so as to minimize the intake resistance.

Extended data:

Precautions:

1. The sensor shall be installed horizontally or vertically (the fluid flow direction shall be from bottom to top) on the pipeline with corresponding nominal diameter.

2. When the compressed air flowmeter is used for flow regulation, special attention should be paid to installing the flow regulating valve behind the sensor, otherwise it is easy to produce jet when the flow is small, resulting in the fault phenomenon that the medium flow is inversely proportional to the valve opening when adjusting the flow.

3. When the flowmeter is installed, its upstream and downstream should be equipped with a certain length of straight pipe section.

4. The flowmeter cannot be installed on the pipeline with strong vibration, so as not to affect the measurement accuracy.

5. When there is a high-power motor near the flowmeter, in order to avoid power frequency interference, besides shielding the signal transmission cable, the signal transmission mode should adopt DC signal as far as possible.

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