The engine light, although it’s only yellow, shouldn’t be underestimated. If it’s on for a longer period of time, it can mean a serious engine malfunction. What should you do if you notice it in your car?
Manufacturers place several and sometimes even more than twenty warning lights on the panel of a modern car. Their task is to inform about the possibility of a fault in one of the vehicle systems. Depending on how important a potential failure may be, the controls come in different colors. For starters, you should determine what error code is causing it. There are many popular ones, p0171, p0174, p0300, p0305, p0306, p0410, p0420 and the most popular one – p0303 code error, usually caused by either poor quality fuel, low fuel pressure or faulty fuel injector. That’s easy to fix and you should be happy if that’s the cause and not broken or weak fuel pump.
Green and blue are the information lights. They show that the system is switched on. Yellow is reserved for the warning lights. If they are lit, a fault is detected in one of the systems or it is not working properly. If they burn constantly, it is a sign to make an appointment for a workshop visit. The most serious defects are indicated by red lights. They usually indicate faults in the most important components of the car, such as the brake or lubrication system.
The engine light has the form of a piston engine contour, or in some older models, it is simply the word “check engine”. It appeared permanently in modern cars in 2001, when mandatory self-diagnostic systems were introduced. In simple terms, the whole idea is to fill all vehicle systems with hundreds of sensors transmitting signals of correct or incorrect operation to the central computer. If any of the sensors detects a malfunction of the controlled component or its part, it immediately reports it. The computer, on the other hand, displays information about it to us in the form of an appropriate control assigned to the error.
Errors are divided into temporary and permanent ones. If the sensor sends a one-time error, which doesn’t appear later, the computer usually extinguishes the light after some time, e.g. after the engine is turned off. If, however, after restarting, the light does not go out, it is a signal that you are dealing with a fault. Control computers receive information about errors in the form of codes set individually by each manufacturer. Therefore connecting the service computer helps to determine the place of failure, sometimes even indicates a specific problem.
The engine control is responsible for any irregularities that are not attributed to other controls informing about faults under the hood. It is yellow in colour, so there is no need to panic when it catches fire. As with other controls, the error can be temporary or permanent. If it goes out after some time, it may mean e.g. a single drop of the ignition or too low voltage in the installation during the start-up. Worse than when it is restarted, it will still burn. This may already mean a malfunction, e.g. damage to the lambda probe or catalytic converter. Such a situation cannot be underestimated and, if possible, you should go to a workshop to diagnose the error.
Lighting of the engine light often occurs excessively in cars with amateur-mounted gas installation. This is not a normal situation and should not occur. If the “check engine” light is on, it’s time to visit the “gas engineer”, because it’s necessary to adjust and sometimes even replace incompatible components.
It’s not wise to drive with the engine light constantly on, especially if you don’t know what the problem is. This can cause increased fuel consumption, engine malfunction, only a system of variable camshaft phasing (if any), and consequently can lead to a more serious malfunctions. You must immediately go to service when the yellow light is accompanied by the engine going into emergency mode. You will recognize it after a significant drop in power, limited maximum revolutions, and even after a drastically reduced maximum speed. Such symptoms are a sign of serious failure, although it is often caused by a defect in the EGR exhaust gas recirculation valve or a failure of the ignition system.
Important information for people who want to buy a used car. After turning the key to the first position, or in cars equipped with the start-stop button, after briefly pressing the button without pressing the clutch pedal (or the brake at the automatic transmission), all the lights on the instrument panel should light up, after which some of the lights will go out before starting the engine. This is the moment to check whether the engine light is on at all. Some dishonest dealers disconnect it when they can’t deal with the fault and intend to hide it. Disconnecting any of the controls is a sign that the car may be after a serious collision and the repairing workshop did not manage to repair it professionally. In cars with a gas installation this may mean installing an emulator responsible for extinguishing the “overexcited” control. It is better to avoid such cars with a wide arch.