Nissan Repair: 1995 NISSAN PATHFINDER OXYGENS SENSORS, fuel pressure regulator, oxygen sensors

Question
QUESTION: I HAVE A 1995 NISSAN PATHFINDER V6 4WD 3.0 ENGINE. I NEED TO KNOW WHERE ALL THE OXYGEN SENSORS ARE ON THIS VEHICLE. WANT TO REPLACE THEM BECAUSE THE TRUCK HAS 135,000 MILES AND HAVING BAD GAS MILEAGE LATELY. HAVING NO ISSUES WITH THE VEHICLE OTHER THAN THAT. THANKS

ANSWER: Tommy,

It is a good idea to replace the oxygen sensors with the number of miles you have.  I would replace the front two.  There is one on each exhaust manifold, or close to them.  But, I bet your lower mileage is due to more than just them.  I would replace the fuel filter and check the fuel pressure to make sure it is correct and you have no leaky injectors and the fuel pressure regulator is working properly.

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QUESTION: THANKS FOR THE GREAT ADVICE, ONE OTHER QUESTION, THIS WILL WILL BE MY FIRST TIME REPLACING THESE OXYGEN SENSORS, IS THERE A SPECIAL TOOL TO REMOVE THEM? OR JUST USE A WRENCH? SPRAY ANY LUBRICATE ON SENSOR TO LOOSEN THEM ALITTLE? DO THEY COME OUT EASILY USUALLY. THANK YOU FOR ANY ADVICE ON THE QUESTIONS.

Answer
Tommy,

WD40 works great.  Most oxygen sensors have doped threads so you will not need a sealant.  A special oxygen sensor socket is available at most parts stores for removal and installation.  It is cut down the side to clear the wires.  They do come out easy much like a sparkplug.