code p0420 new pathfinder owner

[michael9250]

My name is Michael I am new to this website and have a couple questions i can hopefully find answers for.I just purchased my pathfinder a month ago and it has been a great car.(Been wanting it for a long time) Yesterday my service engine soon light came on and after taking it to autozone i was informed it was code p0420. After calling my mechanic who is a good friend he told me that It was more than likely one of my catalytic converters. I do not know much about cars but he said that it is an expensive proposition. I am having him look at it tommorow but I was wondering if anyone here has had the same code or problem or knows anything about it. I am very upset because this is not covered under my extended warranty and I just bought the car. The vehicle has 62000 miles on it and drives well. I am also wondering at this many miles what would be some maintenance recommendations to do at this point. I would more than appreciate any answers you guys may have for me and I thank you in advance

[alexf20c]

the P0420 DTC is a common one, and it means your bank-1 catalytic converter is below threshold. that doesn't necessarily mean it needs to be replaced; it just means the computer thinks it's not working as well as it should. (this reading is obtained by the downstream bank 1, sensor 2 Oxygen Sensor.)

i get this code all the time. it comes on randomly, then disappears just as quickly as it came. it usually stays on a day or two for me. this DTC (diagnostic trouble code) does not affect engine performance. it does, however, affect the environment.

i've yet to replace my catalytic converters because like your mechanic said, it is very expensive. i just wait for the code to go away (the computer will retake the test and if you pass, it will turn the code back off). if you've got the money and you're anal about things, go ahead and have it replaced. like i said, the only thing being harmed is Mother Nature - not your truck.

for normal maintenance, at 60k miles, i'd recommend the normal stuff like air filter, fuel filter, oil change, plus things that make a basic tune-up. you'll want to change your spark plugs (use NGK OEM), distributor cap and distributor rotor. it wouldn't hurt to replace the PCV filter either. run a bottle of fuel system cleaner through the gas tank.

[Buzzman]

Good advice Alex.However, I should point out that he shows in his avatar that he has a 2001 Pathy.This is the first year that it came equipped with the 3.5 engine, and there are noticeable differences.There are no plug wires/distributor or stuff on this engine. It has ignition coils.Changing the plugs is still a good idea though, especially if it still has the original ones in there.Also, the PCV is a royal pain to replace on these things.You have to remove the intake plenum assembly to gain access. Not worth the trouble unless there's something actually wrong with the PCV.I still have the original PCV in mine. So far so good.All your other suggestions are good.Thanks.