Check Engine Light Diagnostics
Check Engine Light Causes
There are multiple issues that make your check engine light come on. As we mentioned, a loose gas cap causes the computer to read a problem. Simply giving your gas cap a few turns should fix it. If it doesn’t, there could be more severe issues. One of the more common issues is a leak in the O2 sensor. The O2 sensor measures the amount of unburned oxygen that is in the exhaust system. If the O2 sensor is damaged, it will trigger the check engine light. You will need to get it replaced. A bad O2 sensor reduces fuel mileage and the overall performance of your vehicle.
Another issue that causes a check engine light is an EVAP or a vacuum leak. The EVAP system functions to keep gas fumes out of the tank. They also help to reduce pollution and keep you from smelling gas inside your car. If there is a leak, usually caused by a loose o-ring or seal, you may start smelling gas in your vehicle. When this happens, it’s time for a repair. A vacuum leak occurs when there is a broken or loose hose going to your engine. You could experience issues starting your vehicle or stalling.
The catalytic converter keeps harmful gases and pollutants away from the engine. If this part is faulty, it will severely affect your vehicle. Your fuel mileage decreases, and you will fail your next emissions test—the only fix for this is a complete replacement. If you have a flashing check engine light, you must take your car to a shop immediately. A flashing light indicates an engine misfire. There is a major malfunction in your system, and your vehicle is dangerous to drive.