Idle jitter of waiting red light on the mall

The engine has serious carbon deposition. Check the spark plug.

Serious carbon deposition in the engine: The most common reason for car jitter is that the throttle valve is too dirty or the nozzle has too much carbon deposition. When there is too much carbon deposit in the engine, the gasoline sprayed by the fuel injection head will be absorbed by the carbon deposit during cold start, which leads to the lean mixture during cold start and makes it difficult to start. In this case, only when the gasoline adsorbed by carbon deposits is saturated, the car will simply start. After stopping, the gasoline adsorbed on carbon deposits will be sucked into the cylinder by the vacuum suction of the engine for combustion, which will thicken the mixture and dilute the combustible mixture of the engine, resulting in idling jitter after cold start. The lower the temperature, the more oil is needed for cold start, and the existence of carbon deposit will affect the stability of cold start.

Solution: Clean the oil circuit, check whether there is carbon deposit in the idle motor and clean it.

Check the working conditions of spark plugs, high-voltage lines and ignition coils. The ignition system is not easy to use, and the spark plug is not in good condition, which will also lead to this failure.

Solution: Check whether there is too much carbon deposit in the spark plug and replace the spark plug.