I'm looking to replace my oxygen sensor but I'm looking to buy the part online and I see %26quot;before catalyst%26quot; and %26quot;after catalyst%26quot; oxygen sensors.... which one do I need, where is it located, and do I have to take it to a shop or can I do it myself?
Where is the oxygen sensor in a 2002 nissan frontier %26amp; how do I change it?
If you look at your exhaust pipes and follow it down, there will be what looks like another spark plug connected to the exhaust pipes / headers / manifold. This is the O2 sensor. You will need a special O2 sensor removal tool. It can be rented (or loaned) from Autozone for free (most of the time).
There's another one just like it AFTER the catalytic converter.
You can find video on how to here:
http://www.advanceautoparts.com/english/鈥?/a>
search to 3rd page and click on %26quot;DIY - Oxygen sensor%26quot;
Good Luck
Where is the oxygen sensor in a 2002 nissan frontier %26amp; how do I change it?
there are two one before the CAT and one after. you need to replace both if you cannot test to see which one is bad. Are on the exhaust pipe. Unplug the connection and unscrew the sensor. Follow the instructions to install the new. I would not buy on line just go to any auto zone or kragen to buy as they can help advise you how to remove and install. plus make sure you get the correct ones.
i would suggest not to buy a universal sensor as i have experience many uni sensor not being up to par on imports
If you don't even know which one you need, how do you know you need to have any of them replaced (your vehicle probably has 4)? Is your Check Engine light on and your just assuming that's the problem? If so your going to waste a lot of money. Did you have someone %26quot;code read%26quot; it and come up with an O2 sensor related code? Those codes do not automatically mean you need to replace the sensor. It may mean there is another problem that is in turn causing the sensor to read outside of its normal range.
My suggestion is to take it to a shop to have whatever problem it is you are having properly diagnosed. It is much cheaper than throwing parts at it until you get lucky and get it right.
