What is the reason for the failure light of BMW 5 Series engine?

1, poor combustion of mixed gas: engine spark plug failure, ignition coil failure, fuel pump failure, oil circuit blockage, etc. It will cause poor combustion of the mixture. The problem of engine carbon deposition or knocking caused by poor combustion of mixed gas is monitored by the oxygen sensor of the engine and transmitted to ECU, and then the fault light is lit to display a warning.

Solution: Find a professional to repair it.

2. Sensor problems: including water temperature, crankshaft position, air flow, intake air temperature, oxygen sensor, etc. When these sensors are damaged, the contact is poor or the signal is interrupted, the ECU of the automobile can't get the engine data accurately, which leads to the engine fault light.

Solution: Replace or repair the sensor.

3. Maintenance problem: Poor engine maintenance is the most common cause of engine failure.

Solution: Let the maintenance personnel check the engine.

4. Oil quality problem: Generally, the fuel filled in automobiles is labeled, and the engine oil is also divided into semi-synthetic and fully synthetic. Manufacturers generally advise car owners which brand of fuel and which type of engine oil to use. If the owner does not add it as required, it will cause the engine to wear for a long time and cause the fault light to light up.

Solution: Change the oil.

Extended data;

Matters needing attention in engine maintenance

1, clean the air filter

The air filter is directly related to the air intake of the engine when the car is running. The manager of Guangben dealership told the reporter that the air filter will not be blocked when the car is only driving in the urban area, but if the car is driving on dusty roads, it is necessary to pay special attention to the cleanliness of the air filter.

2. Remove throttling sludge

There are many reasons for sludge at the throttle, some of which are carbon deposits formed at the throttle by exhaust gas from fuel combustion. Then, impurities that are not filtered by the air cleaner will remain on the throttle. Too much sludge will cause air resistance and increase fuel consumption.

3, clean up the nozzle carbon deposit

Because the combustion chamber is easy to produce carbon deposit, it is difficult to start; Carbon deposition in the fuel nozzle will also lead to oil blockage, gasoline injection deformation, poor atomization, and fuel consumption will naturally increase.