The most common reason for a check engine light to come on in the 2009 Ford Focus is a loose gas cap. If fumes leave the tank through a loose or cracked cap, they will trigger the light. In most cases, fixing the cap will turn the light off, but if it doesn't, You may have a different issue that needs addressing or the light needs to be reset by a mechanic. A failed oxygen sensor is another common problem. If left alone, damage can be caused to the catalytic converter and spark plugs. This also reduces Your fuel economy. A Bad mass airflow sensor is another issue You could be facing. This sensor measures the quantity of air in the engine to determine the amount of fuel that is needed. Additional components that can trigger the check engine light to come on in the 2009 Focus are ignition coil, spark plugs, spark plug wires, fuel injectors, vacuum, and catalytic converter.
Thomas D.
April 9, 2020
If you have an illuminated engine light on a 2009 ford focus, the vehicle could have a wide range of problems. An obvious and common fix is to make sure you gas cap is seated correctly. If that doesn't solve the issue, you'll want to contact a mechanic who can read the computer on the vehicle and find the problem.
lindakirk71@gmail.com
January 19, 2023
We will check cap, are you referring to petrol cap . ? The engine light has come on and stays on. Please help
The Questions and Answers on this page are the statements and opinions of their respective authors and not VehicleHistory.com. VehicleHistory.com
does not research or authenticate any of the Answers provided.