The oxygen sensor checks the level of oxygen within your car's engine. The car's computer uses that information to make sure the fuel-to-oxygen ratio is right to create the best performance. When the sensor starts to go bad, there may be too much of one element, and that leads to the following three signs.
B is For Because The Check Engine Light Turns On
One of the first symptoms you will notice is the check engine light. Don't ignore it. This tells you that something is wrong with the engine and needs your attention as soon as possible.
This light may flash, which indicates the problem is serious. You should consider driving the vehicle to the nearest garage right away. If it isn't flashing, you have time to get to your trusted mechanic.
A is for Always Filling The Gas Tank
Unfortunately, your check engine light won't tell you much until you run a diagnostic, so you'll need to look out for other signs. One of those is the mileage you get from your fuel. If it is poor, it is a sign that your engine isn't performing as well as it should. This could be due to the oxygen sensor not relaying the right information about oxygen levels to the computer. Your car starts to consume more fuel than it should.
D is for Driving with a Rough Idling and Shuddering Engine
When the car isn't getting the right fuel-to-air ratio, it starts to shudder and misfire. You may notice this when you are sitting idle at first. Rather than just ticking over smoothly, with the fan going off now and then, the car will jerk and shudder as the engine tries to deal with the ratio it is being given.
This can develop into problems when you're driving. You may hear it misfiring when driving at slower speeds. When you try to accelerate, the engine stumbles, so you find it harder to get the speed up. In some cases, you may be stuck at the same slower speed until the engine gets the power it needs.
Your vehicle may not pass a smog or emissions test if the oxygen sensor is faulty. You need to get the oxygen sensor fixed – or replaced – as soon as possible to protect your vehicle's engine. As long as you remember the word BAD, you will also remember these three signs that your oxygen sensor is going bad. For more advice, talk to a mechanic.