1. My vehicle has 4 oxygen sensors...how do I know which one to replace.?
2. How important is it to replace it?
3. Will this sensor malfunction effect the engine
4. How difficult is it to replace it
5. How much do they cost?
Thank You for writing into AskPatty!!
To address your concern.
Typically, you can have an a computer hooked up to your ECU, and have a read out of which O2 sensor is malfunctioning.
If you have a faulty O2 sensor it is very important to replace, (you may already have your check engine light on so if you have other unrelated issues to turn your MIL on you will not be aware until your first issue is repaired), One of the most important sensors on a vehicle is the O2 sensor. If you have one that has failed this can "throw off" your air/fuel ration mix and cause your Jaguar to run rich/lean resulting in poor fuel economy. O2 sensor can sometimes be difficult to replace and should be left to a professional if you have not done this procedure before. You may have (2) before and (2) after your catalytic converter. If you live in a salty environment O2 sensors can rust and seize, which can result in breaking off inside the exhaust system.
Prices may vary I recommend calling around for various estimates, sometimes obtaining on on-line is a good option too.
Hope this Helps!!
A. J. Valle
First, normally if you're using a code reader the diagnostic trouble code and definition will indicate which oxygen sensor to replace with something along the lines of "Sensor 1, Bank 1." If your vehicle has a faulty O2 sensor it may seem like the vehicle is running just fine. However, ignoring a faulty O2 sensor will negatively impact your car's fuel economy. In some cases it can deplete MPG as much as 40%. Not only will you eventually have to replace the sensor, but meanwhile you'll be paying more to fill up your gas tank. Ignore it for too long and more serious damage could be done to more expensive parts such as your catalytic converter ($1,000+ on average). The average cost to replace an Oxygen Senosr according to the CarMD Vehicle Health Index is $246. It's also the most common repair.
〉 Answered on May 7th, 2012 by Kristin Brocoff, Director of Corporate Communications at CarMD.com