What are the functions of automobile exhaust one-way valve?

It is mainly to control the exhaust gas involved in combustion, which is beneficial to environmental protection, reduce the emission of nitrogen oxides and ensure that the engine has enough power (too much exhaust gas involved in combustion will make the engine work badly). Respondent: Tang reported that the check valve level of crankcase ventilation was 6: 2013-01-18: 22:19: 09. ② Keep the pressure in the crankcase below atmospheric pressure (78.4kPa for Dongfeng EQ6 100 engine) to reduce oil leakage; ③ Keep the crankcase ventilated and the engine oil fresh. \x0d one-way valve also has a certain relationship with fuel saving. If the engine oil in the crankcase deteriorates, becomes dirty and blocks the check valve, the vacuum degree of the intake manifold will increase with the increase of the throttle opening, so the air velocity at the throat of the carburetor will increase, the oil output of the fuel injector will also increase, and the fuel consumption will also increase.