My wife wrecked my ole 5.0 mustang so I got me a 3.5L fully loaded maxima SE 2005 for only 650 dollars. It had 6 engine codes but I've got her down to one code and its oxygen sensors. I already pulled 1 plug (from the downstream? it was one near the cat.) and it was pretty black. Well im replacing them all, deciding to choose Amazon/Ebay as my destination. I personally located 3 o2 sensors but have yet to youtube the location of the other(s). Is there 4 o2 sensors total? and if so does somebody have a link to a decent bang for buck product? I saw a decent bundle deal for a set of the 2 upstream and 2 down for a little over 100 bucks but being new to a Maxima I don't want to jump the gun. Thanks again guys for having me, Nick.

pic of car
https://postimg.cc/8JwS8wcZ

P.S valve cover gaskets were replaced and indication I got from the sensors is they are all original so i think its smart to just replace them all (156k miles), if you think otherwise Im open to opinions. This car was in pretty rough shape even the rack and pinion was installed wrong (according to a mechanic that worked the initial 6 codes) I have a power steering hose leak hes going to finish sometime this week and im sure its in large part to the stress that has to be put on the wheel when you turn sharp rights. ( THE CAR LITERALLY CANNOT COMPLETE A HARD RIGHT TURN PARK IF THERE IS A CAR IN ANOTHER STALL ) I'm told by the mechanic its the rack and pinion. Not that its necessarily bad or going to cause damage but ill be stuck with that annoying nuisance when I turn right because of it being incorrectly installed at some point by the previous owner. at least that's what I understood it as when the mechanic explained it to me. All in all I love the car just want to get her conditioned because she's been neglected to long.

 

I say either ignore the codes for it as it doesn't cause any problems. Or get the plug-in on the O2 sensor that will fool the ECU into thinking all is fine.
Replacing all the O2 sensors isn't worth it on a car that old with lots of faults going on. have you checked on replacement O2 sensor $ yet? they aren't cheap for 4 of them (at least in Australia).

 

Bank 1 sensor 1 and Bank 2 sensor 1 are used for air/fuel. The other two sensors only monitor cat efficiency and don't affect anything. Nice find with the '05. I spent more on my 5th gen's alternator.

 

thanks brother, I did a lot of studying on the o2 sensors, I was able to find and locate the 2 downstream and 2 upstream.

bank 2 upstream was a pain to find , all sensors replaced except b2s1 (getting her done tomorrow) but so far engine light hasn't came back on. she still needs a serious look as far as power steering. The shop said some odd stuff about how the rack and pinion replacement was installed by previous owner. I don't have full radius right turns, for regular road driving the right turn, for the most part is ok. Its tight nit areas like u-turns or parking where you feel the wheel come to an early stopping point. I feel like this has caused the current hose leak and am getting a full diagnosis on power steering tomorrow. All in all I've either had or personally replaced 6 vcgs, 4 coil packs, spark plugs, 2 downstream o2s, 1 upstream b1s1, air filter, oil change and she sounds good and flys like a new car not even a loose strut. ( outside of a weird hum quiet enough that you can only hear it at low rpm/speed, but not to alarmed because im ocd. But... the sound is surely there, not sure if that's just the engine or possibly power steering, this is my first foreign car lol).

but yea dude I even realized how bigger the steal was when I looked into these vq35 engines, it sounds like an iconic part of Nissan/Infinity line up.

 

my thought process into replacing both upstream and down was I knew replacing 1 at a time is just causing more expenses. I was able to get a bundle deal on 2 bosch upstream, 2 ntk down?(correct me if im wrong on name) for $233.00. something that potentially could of costed me 50% more had I of replaced 1 sensor at a time. they were all in rough shape upon removal and I'm willing to bet the engine light will kick back on until I replace b2s1 tomorrow. From what I understand downstream o2's don't usually trip the engine light but I like my car crisp and smooth, those things were black upon removal and only took 15-30 minutes to replace them tbh.

*EDIT* FYI all engine codes are cleared as of now, the last 1 left was oxygen sensors but it didn't specify. Shop already replaced b1s1, I'm going to replace b2s1 and that's all I have left outside of power steering. im $1700.00 in on repairs but when you factor in I paid 600 dollars for the car, I have enough upside to ask ATLEAST $3,500, but with the wiggle room allotted I would rather have a solid running car that the banks don't own. The more things I replace that need replaced, the more life I'm going to get. ( I know to a certain extent I have to pump the breaks because at the end of the day an 05 is an 05 but this baby is clean and fully loaded outside of some body and paint touch up) Not a tear in the leather, interior is flawless outside of normal aging.

 

Bank 2 sensor 1 is the easiest one to locate. It's practically staring at you once you pop the hood. You can easily check bump-to-bump steering by jacking up the car and watching the pins on the steering knuckles make contact with the stop plate on the lower control arm. That hum is going to be your power steering pump, from whatever grease monkey jacked with it last. No big deal.

And yes, the VQ is a highly regarded engine. Nissan used it in everything. Unfortunately, after '02, we have powerplants that were produced after Renault bought Nissan and f$cked everything up, so keep up on your maintenance. The car still has life if it was at least semi-maintained and you give it some love once in a while. I like the 6th gen body style. I had fun with a 5sp 6th gen for a bit back in '07-'08.

 

thanks for the timely response, I get the sense at one point along the **** stick of owners there was a decent one. The interior integrity showed me, atleast a sense of respect for a long time. From what I'm seeing is there was a minor front end collison, ( as per shops statement) that required headlight replacement, a new front bumper, and rack and pinion. all which were potentially installed wrong. ( smelled burning wires one time upon initial start up when I turned headlamps on, also when on auto they do not turn off after I kill the ignition and lock the car. waiting to smell burning wires again and or something that tells me the headlights need immediate attention. ) Early overall indications say regular upkeep and a few surprises along the way, but shes got a lot of life left. Thanks for your timely response, I as well enjoy the 6th gen body style, more so towards the rear end design.

 

lol ,that is facts for you boy.