However, a low fuel level *could* indirectly contribute to a check engine light in a few very specific and unusual ways:
* Faulty Fuel Level Sensor: If the fuel level sensor is malfunctioning, it might send incorrect readings to the car's computer. While this wouldn't directly trigger a check engine light related to the fuel *level*, a consistently inaccurate reading could cause problems with the fuel system's calculations. This could lead to other issues (like running lean or rich) that *would* trigger a check engine light. A low fuel level might exacerbate a faulty sensor's inaccuracies, making the problem more noticeable.
* Fuel Pump Issues (indirectly): A nearly empty tank might expose a weak fuel pump. If the pump is already struggling (due to age or wear), the low fuel level could further strain it, causing it to malfunction and trigger a code. Again, it's not the low fuel itself causing the light but highlighting a pre-existing problem.
* Loose connection near fuel pump: A low fuel level might cause some stress or movement near the fuel pump, and if there is a already loose or poor connection in that area, the low fuel might cause a break in contact resulting in a code.
In short: The fuel level itself is not the problem. The check engine light is likely indicating a separate issue (often related to the fuel system) that's either made worse or more apparent by the low fuel. You'll need to get the code read from the car's computer (using an OBD-II scanner) to diagnose the actual problem causing the check engine light. The low fuel is just a coincidence or an exacerbating factor, not the root cause.
