Why is My Check Engine Light On?

There are few more stress triggering things than looking down at your dashboard and see your check engine light on. Unfortunately, there’s no easy answer as to why it might be on. It could be something simple like you didn’t tighten your gas cap the last time you filled up or something more serious. The only real way to find out exactly what’s going on is to go to your local mechanic and have them connect the computer and run a diagnostic. However, there are a few common reasons your check engine light may be on.

O2 Sensor

The O2 sensor is one of the tools your car uses to burn fuel efficiently. It measures how much unburned oxygen is in your exhaust. When it fails, it can impact your car’s fuel-efficiency. If you don’t have your local mechanic replace it in a timely manner, you can cause damage to your catalytic converter and spark plugs. The average cost to replace your O2 sensor is about $250.

Bad Spark Plugs and/or Spark Plug Wires

In a previous blog, we talked about the importance of replacing your spark plugs in a timely manner. If you haven’t replaced yours, you may end up with your check engine light on. If you notice your engine is missing or your fuel economy has dropped and your check engine light is on, you might have an issue with your spark plugs. Your local mechanic will charge about an hour’s labor plus the cost of the plugs.

Mass Airflow Sensor Issue

Because the mass airflow sensor (MAF) determines how much fuel your engine needs, it’s going to set off the check engine light when it’s not working. A bad MAF can damage other parts of your engine so don’t let this go unchecked. You’ll notice poor fuel efficiency goes along with a failing MAF. This can be a pricey repair, costing as much as $400.

Failing Catalytic Converter

When you don’t change your spark plugs or replace your O2 sensor in a timely manner, your catalytic converter will fail. The catalytic converter changes the carbon monoxide into carbon dioxide which protects the environment. One sign that it’s failed is that your car runs hot. This is the most expensive of these common reasons for your check engine light to be on costing from $1000 – $3000 depending on your car’s make and model.

The lesson here is don’t put off having your check engine light’s reason for being on evaluated. It just takes your local mechanic a few minutes to diagnose the issue and the sooner you get it repaired, the less likely more damage will happen. If you don’t have a local mechanic you know and trust, call Oldsmar Automotive at 727-784-3501 or come by 3166 Tampa Road on Oldsmar for a diagnosis of your system.