Oxygen sensors detect the amount of oxygen in the exhaust. Oxygen sensors usually don’t have a replacement schedule. A bad oxygen sensor can be diagnosed with a code reader or scan tool. A car’s ...

We've all experienced a check engine light coming on, knowing that unless it's taken care of immediately, it'll be a nagging long-term problem in the back of our minds. It's one of the most important ...

Thanks to modern fuel injection, the engine computer has extremely precise control over the proportions of the air/fuel mixture inside the cylinders. A countless number of sensors around the car tell ...

Question:I have a 2001 Nissan Pathfinder with the 3.5-liter V-6. The check-engine light came on, and I had code P0420. I was told it was a bad catalytic converter, so I went ahead and replaced it ...