Nissan Repair: 99 nissan quest po141,po325 codes, oxygen sensors, oxygen sensor

Question
Hi Von During my search I came across you had the exact same codes I do with my Quest and was wondering did the new coil fix the problems or was it something else. Codes PO141 and PO325. Any help would be greatly appreciated.
Thanks Jon

Answer
Jon,

What the codes mean are as follows:  The P0141 is the rear oxygen sensor heater circuit that is causing the code.  I would replace the oxygen sensor.  Remember that there are three oxygen sensors.  They usually fail at around the same time.  I know it is expensive but I would replace all three.  Also, there is a relay that is timed to heat the oxygen sensors.  Now, since the code is only showing one I would assume it is the oxygen sensors instead of the relay.  I ahve a 2000 Maxima SE and had the same code and replace the rear oxygen sensor and shortly after that the other two oxygen sensors failed.  So, just bite the bullet and replace all three.  You can do this yourself since they unscrew like sparkplugs and just plug in, if you get the factory style.  I would not purchase aftermarket ones that have to be soldered in.  It is too easy not to get the length right and if corrosion gets to the soldered joint you are looking at more problems down the road.  rockauto.com or courtesyparts.com are two great sources for about half of the dealer price.  Second is the code P0325 for the knock sensor.  I do not know why Nissan's seem to eat knock sensors but they do.  The intake needs to be removed to get to the knock sensor and it is time consuming but you could do that yourself too.  Again, check out the two sites I have provided since they are a cheap alternative to the dealer.