How can I tell if I have a bad oxygen sensor?

Answer by  NateB (571)

Typically when an oxygen sensor goes bad it will kick on the "check engine" light. If the light is on then most auto parts stores can tell you what made it go on. If it's not on then they should be fine.

Answer by  nhoffer (27)

The check engine light would come on for a couple minutes, then go out, car ran fine, but I had poor gas millage. 150 miles from a tank! They put the select monitor on and it came up O2 sensor failure, changed it and started getting 220 - 230 miles from a tank!

Answer by  Allstar (2071)

If you have a bad oxygen sensor, the ECM should kick up a check engine light. The OBDII system should kick up an emissions code as well. Easiest way to tell is to take the car to a shop and have it scanned.

Answer by  okaylumberjack (83)

Here are a few of the common symptoms of a bad oxygen sensor: 1. Rough Engine Idle 2. Engine Missing 3. Engine Pinging 4. Poor Gas Mileage 5. Increased Vehicle Emissions

Answer by  chazeloff (324)

If you have a bad o2 sensor then you car should throw up a service engine soon code. you can check the code with a obd2 scanner.

Answer by  kate74 (273)

You can take your car to a local auto parts store. Ask them to do a diagnostic check, which they'll do with a machine, usually for free.

Answer by  BruceWayne (113)

Sometimes it will throw a code if it isn't working at all but if it has just lost efficency then it won't throw a code but you will have worse fuel milage then one that is working properly. A good rule of thumb is to replace them every 60-100K mi.

Answer by  bb (674)

check to see if your local mechanic has a scanner to check the car with. the scanner will tell if the sensor is bad.

Answer by  Amber40 (24961)

The best way to tell is with a code reader. If the sensor is bad then the computer will give a code. Just have a shop scan it for you.