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replaced fuel level sensors but still has light on and no gas gauge
1:When the engine fault light is on, the most likely reason is that there is something wrong with the fuel emission system, and the most likely problem in the emission system is the oxygen sensor. The oxygen sensor is installed on the exhaust pipe and is divided into front and rear groups, which are respectively located in the front and rear of the three-way catalyst to monitor the oxygen concentration in the exhaust. The engine computer can judge the combustion condition through the front oxygen sensor, and can also judge the working state of the three-way catalyst by comparing the concentration difference between the front and rear oxygen, so as to ensure that the emission meets the standard. If there is a problem with the oxygen sensor, the engine fault light will come on. The solution is to clean or replace the damaged oxygen sensor. The preventive measure is not to use inferior gasoline or inferior fuel additives.
2: There is something wrong with the three-way catalyst. It's still the problem of the fuel emission system, but this time it's replaced with a three-way catalyst. The function of three-way catalysis is to reduce pollutants in exhaust and purify tail gas. If the three-way catalyst is blocked, poisoned or damaged, the purification effect will be affected. Once the abnormality is detected by the oxygen sensor, the engine will turn on the light. The solution is to clean or replace the three-way catalyst. The prevention method is also not to use inferior gasoline and inferior fuel additives. In addition, it is not recommended to remove carbon deposits too aggressively for old cars, so as to avoid blocking the three-way catalyst after large carbon deposits fall.
3:There is something wrong with the intake system. The combustion of the engine requires air, so when there is a problem with the intake system, poor combustion will occur and the engine fault light will be on. Common problems in the intake system include air filter blockage, throttle failure, turbine failure, air flow sensor failure, intake manifold leakage, variable intake manifold mechanism failure and so on. The solution is to solve the problem of air intake system by plugging, dredging or replacing components. Since most of the faults of the air intake system have nothing to do with maintenance, the only thing we car owners can do is to replace the air filter according to the maintenance manual, generally every 10000 kilometers.
In short, there are many reasons why the engine lights up. The correct way is to send the car to the 4S store or garage for inspection as soon as possible, but if you don't pay attention to it or repair it indiscriminately, I'm afraid you'll have to drag a small problem into a big problem.
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