Why the Check Engine light comes on more often in the winter

Activating the warning does not always indicate a motor problem

In cold weather, the car’s engine experiences increased loads and any trifle or saving of fuel and lubricants can create problems. Some of them are indicated by the Check Engine light, which often lights up unexpectedly. What faults can this indicator show and should the driver worry about them?

The “test” lamp usually flashes after the electronics have detected an error in the operation of the engine or gearbox and stored the error code in memory. Quite often such surprises occur in winter, especially with sudden changes in temperature. One of the causes of these problems can be “bugs” in various sensors, due to the fact that moisture or condensation gets into their contacts.

Used cars most often have problems with the mass air flow sensor (Mass Air Flow Sensor, MAF). Over time, its contacts rust or rot as cold and moisture do their job. As a result, errors occur in the operation of the power system and due to them the electronic control unit begins to use medium settings, rather than those set for operation in cold climates.

As a result, fuel consumption increases with the Check Engine light. If you do not pay attention to this, there is a risk of carbon deposition on the valves and pistons, which over time will lead to serious engine problems.

The “engine check” lamp may also light up due to the fact that the tank cap has not been tightly closed at the service station. The reason for this is often a very small piece of ice, which prevents closing. Then the system loses its tightness and the warning lamp is activated.

Another reason for the warning signal may be the driver’s attempt to save money by refueling at a gas station where fuel is cheaper. This can cause it to run on dilute fuel, which will be detected by sensors and activate the “Check Engine” label.

Sometimes it happens that the light is activated when starting the engine after a frosty night. Initially, the car runs at high speeds, which the system lowers when it reaches operating temperature. Several different sensors are involved in this process, and even if only one of them emits periodic signals, it is quite possible to activate the test lamp.