P0141 O2 sensor question
 

So I read this code and I know which O2 sensor it refers to. My question is whether or not replacing the sensor is the problem or if that's just the sensor that's picking up some other problem. I hate to start just tossing parts at it if it could be something else.


2001 Galant ES V6

I talked to several Auto Technician and they said it is better to have Engine Diagnostic.
it will cost about $100.00 it will give the exact problem not only the 02 sensor or it might not be 02 sensor. very complicated problem with sensors

I have the same problem with my 2008 Lancer 02 sensors.

Update:
Two days before the check engine light popped on, I happened to be working on repairing the battery negative cable. According to http://www.obd-codes.com/p0141 the cause could be the sensor itself OR "an open or short to ground in the wiring harness".

I've cleared codes and driven around 20 miles to get the readiness tests all reset and all are showing OK/ready with no trouble codes. I'm wondering if removing the battery and jostling the cables/harness around along with cleaning the area with some baking soda solution just caused a brief grounding problem somewhere. Supposedly the O2 sensors are ultra sensitive to just about anything.

I'll post back if anything else changes, but I think I'm good to go.