How is the fuel consumption of Audi A5 doubled after replacing the same type of spark plug?

First, general spark plug problems will lead to poor engine operation, such as difficult starting, unstable idle speed, poor acceleration, sudden refueling and tempering, excessive exhaust, and increased fuel consumption. If the engine has serious carbon deposition and the valve is not tightly closed, so that a cylinder cannot work completely because there is no cylinder pressure, or even the valve does not return. At this time, the valve and piston will interfere with each other and eventually damage the engine. It can be seen that the influence of carbon deposition on the engine is very huge.

Second, the solution

1. Gently unplug the high-voltage wire connector, and don't shake the insulator of the spark plug forcibly when working, otherwise the sealing performance of the spark plug will be damaged.

2. The engine can be disassembled after cooling. When the spark plug to be disassembled is unscrewed, clean the dirt around the spark plug one by one with a thin hose to prevent the dirt from falling into the combustion chamber after the spark plug is unscrewed.

3. Around the screw, the spark plug electrode and gasket must be kept clean, dry and free of oil pollution, otherwise it will cause electric leakage, air leakage, spark weakening and other failures.

4. When installing, aim the spark plug at the screw hole with a sleeve, screw it in gently by hand until it is about 1/2 of the total thread length, and then tighten it with a booster. If the hand feel is not smooth when tightening, check whether there are impurities in the positioning screws or threads, and never tighten them blindly, so as not to damage the screw holes and the cylinder head, especially the aluminum alloy cylinder head.

5. Tighten according to the required torque, too loose will cause air leakage, too tight will make the gasket lose elasticity and also cause air leakage. It is especially important to observe the tightening torque because there is no washer in the conical spark plug.

6. When there is carbon deposit on the spark plug and the oil deposit is not serious, it can be soaked in gasoline, kerosene or acetone solvent. After the carbon deposit is softened, clean the carbon deposit on the electrode and the cavity between the porcelain core and the shell with a nonmetallic brush, and dry it with compressed air. Never scrape with a knife, sandpaper or gasoline to avoid damaging electrodes and porcelain insulators. Check the spark plug gap after cleaning.

Third, prevention methods.

After completing the above, carry out installation and debugging, remind the owner to do regular maintenance and keep the oil and gas road clean; It is suggested to clean the air cabin (replace it according to the actual situation), the throttle valve and the burner every 4000—8000KM (according to the vehicle use and actual situation); Clean the intake throttle combustion chamber and related oil circuits every 15000-25000 km (according to the use and actual situation of the vehicle), check the gasoline grille and replace it as appropriate; Avoid idling for a long time, stop the engine immediately after driving at high speed, avoid driving at high speed immediately after starting, and avoid shifting gears at low speed.