Since its release in 1998, the Ford Focus has been a popular compact sedan and hatchback. Some special versions such as the ST and RS drew great attention from enthusiasts. Unfortunately, Ford canceled all cars other than the Mustang and Fusion in North America to focus on its trucks. So, if you love your Ford Focus, you will need to take care of it. Learning some basic maintenance such as changing Ford Focus oil filters may be a smart idea.
Why Does a Focus Need Airflow?
As you likely already know, your Ford Focus works by igniting fuel in the engine. Like any other combustion, this requires three ingredients: fuel, oxygen and a spark. Fuel comes from your tank and the spark is provided by spark plugs. The oxygen is sucked it as air from the outside. Your vehicle needs to know how much air is coming in at any given time. So, it measures the mass of the airflow.
What Is a Mass Airflow Sensor?
The MAF sensor is a small device attached to the air intake that aids with that important calculation. It features two major parts, a wire and an electrical resistance meter. The wire extends into the air intake. As air passes over the wire, the friction heats the wire up. Thus, it is called the “hot” wire.
To determine the heat of the wire, the meter checks the electrical resistance. As mental is heated, its resistance increases. Therefore, the sensor can reliably calculate the mass of the air passing through the intake simply by measuring its resistance.
In some cases, vehicles have a “cold” wire for calculating outside air pressure. This is less common but may be used for performance vehicles such as the Focus RS.
What Are the Symptoms of a Bad Mass Air Flow Sensor?
The symptoms of a bad MSF sensor include the common effects of an incorrect fuel/air mixture. The vehicle will have rough acceleration, rough idling and may stall immediately after starting. The car will run either rich or lean depending on when the sensor failed.
Of course, the most obvious symptom of a bad sensor is the check engine light turning on. Since the MAF system related to emissions, it will set diagnostic trouble codes when it fails. These can be checked easily use an OBD-II reader.
You can also check the system more minutely by using a multimeter to measure the voltage and frequency of the sensor. This is a good idea if you suspect a problem because the issue may not be with the sensor itself. For example, there may be a problem with the wiring harness connected to it.
Fix Your Ford Focus
Working on your Ford Focus will help you keep it on the road for many years to come. With a few Ford Focus auto parts and some basic tools, you can quickly learn to do a lot of maintenance yourself. Plus, you will enjoy the rewarding feeling of having fixed your own car. So, the next time you need an oil change or a repair, give it a try yourself.