Thread: p0141/o2 sensor questions

hello, i did some searching and found out the p0141 code my engine is now getting is caused by a bad after cat oxygen sensor, or a bad connection between that sensor and the pcm. Is that pretty much the case?? are those the ONLY 2 possibilities, or is there a chance it could be something else??

also, as some of you may have read in my other thread, i just got my car back from the shop on thrusday. it kept throwing a p0171 which was caused by the intake plenum having a hole melted through it right above the EGR port. the shops only guess was that the previous owner let the cat get way to bad before having it replaced. (the cat/exhaust pressure tested perfect)

one of my questions is, since this code was thrown less then a day after getting my car fixed. could it have been possible my p0171 issue was preventing this p0141 issue from being noticed? and now that that is fixed, the pcm can now recognize this problem? is that a possiblility??
im also wondering, IF the previous owner let the cat get way to bad, would that cause the sensor to go bad faster?
and finally, how hard are these to change? are they easy to get to? i took a glance underneath the car and couldnt see it anywhere....

well after looking under the hood i noticed that when i went to check the air filter the other day, the black rubber intake tube that goes from the throttle body to the air filter box and become disconnected right after the air filter box. so for a few days my engine has been taking in unfiltered air......
i would guess this has nothing to do with my issue but would like someone elses input on this too...

Hello,


The O2 sensor code is showing that the heater portion of the 02 sensor is not working correctly. There is nothing that can make that go bad quicker than normal. So you're assumption is correct. All that 02 is there for is to monitor the cat to ensure it is working correctly.



The other code is a lean condition code associated with the UNMETERED air entering the engine.




They have nothing to do with each other.




Also on the o2 sensor. There should be 4 wires, the brown two are the heating element wires. So just trace those to make sure there are no cut's in them. If there both cut don't worry about hooking them back up in the right order because they have no polarity.



My opinion is you need to check for what you mentioned (cut wires) and if nothing is found replace the o2 sensor.

i can answer a couple things for someone in the future .. who still owns this ****ty car
I just fixed this code for different problem i had my 05 grand prix. the cable was loose and hanging low. it finally caught something and the wiring harnessess disconnected. i so so ****en lucky it didnt rip everything out.
the sensor is on the exhaust. u dont have to go under the car to see it. but i cant reach it without jacking it up. to find it:
- when ur looking from the front end it's about lined up with the oil filter. maybe <1 ft towards center
-on the side view, its about 2 feet behind the right front tire
i just had to connect it back. if ur sensor/heater is bad, replace it ur self or at a gargae. if u have the cat problem that i had b4 then i hope ur under emissions warranty. get off ur ass and take it into the dealer