ok here gos , i have a 03 base ,replaced motor with an 04 ,the 04 o2's would not plug in my harness so i took the ones out of the old motor and put them in the o4 , now car runs like crap and inside smells like gas bad. running on 3-4 cyl i would guess . i dont have 175.00 ea for new o2's what should i do .? im thinking about building o2 simulaters from radio shack parts list thats floating around the internet.whats a z er to do .

 

dam skippy did i put this one in the wrong place 2 wth

 

Are you talking about your upsteam O2 sensors? If so, I dont see how that would work. Your ECU works on a closed loop basis and used the O2 sensor to determine proper fuel/Air mixture. You can do that with the dowstream O2's since they serve no purpose other than polution.
Mike

 

so you are using the o2 sensors that originally came with your car?

that would be the ones i would use. There is a chance you could have damaged one of the o2 sensors when they were out of the car. It doesn't take a very hard hit to break the ceramic inside of them.

bosch sells upstream o2 sensors for 45$ each on amazon. 15730 is the sensor. You need 2 of them and you have to wire them in. The wires are color coded and it's pretty easy. I just put them in mine.

 

so far i have had my car in 3 shops replaced o2 sensers on top than maflow, had test pipes put on cuz i was told my cats were bad. and i had a guy tell me its in the wireing. what the hell is next . it wont start with the maf pluged in and will only go up to 2100rpm than it acts just like a rev limiter and cuts out gas mileage went 20 to 5 mpg.

 

That sucks man. Are you saying you DID go ahead and buy new upstream O2's and install them and that did not correct your problem?
I understand why the ones out of your 03 dont work, even though the harness is the same, so you need those 04 sensors in the system and since the harness is different and you cant sort out the colors to match it up, seems your only choice is the new O2's, maybe from Bosch like the previous poster mentioned, mike

 

so you have new o2 sensors?

hmm, sounds like it needs to go to nissan and get hooked up to consult. Maybe your TPS. I think a wiring problem could be a possibility also.

 

well problem solved all it was someone for got to put the nut on my alt a nater. wish i would have seen it eary on .thanks

 

bummer, at least it was an easy fix. It still bums you out when something stupid like that goes wrong.