O2 Sensors
 

I am having problems with my O2 sensors. My check engine light will come on for 2 days and stay off for a week and it will repeat the process over again. This has been going on for about 2-3 weeks now. I don't want to spend $60-$180 for 2 O2 sensors if they are not bad. I do have a Flowmaster Super 40 muffler and I heard that that can mess with your O2 sensors. My truck currently has 43000 miles on it. I was about to put some treatment in my tank to see if I can burn off some of the soot on the sensors. What should I do? Has this happened to anyone here?

RE: O2 Sensors
 

i couldnt see the muffler causing a problem... there are no O2 sensors in your system behind the muffler... the one in the exhaust is before the muffler..... I have ran that same muffler on 3 different vehicles with no problems... I would look into something else causing the problem... but a muffler swap wont mess with your o2 sensors....

RE: O2 Sensors
 

Well, first of all, what has made you think that it is your O2 sensors? You really need to get the codes read to know what is going on. It may be something completely unrelated to the O2 sensors.

RE: O2 Sensors
 

Well there are 3 reasons that I know they are my O2 sensors: I know what a rich and a lean running engine's exhaust smells like and I did put a computer on it and it said banks 1&2 have a rich condition and O2 sensors typically only last for 50000 miles and sometimes they go under that (like in my condition) and they can last for many mor miles than that. I figured it wasn't my muffler messing with it and I do know where that are located on my truck: before my exhaust joins together to go into my cat.

RE: O2 Sensors
 

Well, a rich condition can be caused by many, MANY more things than a bad O2 sensor. Like maybe a bad FPR... Can your computer look at the sensor data? If it can, take a look at the response from the O2 sensor as well as the IPW (injector pulse width) and the STFT & LTFT (short/long term fuel trim). If you cannot see this data, then I would at least grab a fuel pressure tester and do a leak down test to make sure that it isn't some extra fuel getting past the injectors or FPR causing the condition before you drop the $$$ on O2 sensors.

RE: O2 Sensors
 

Ok, I will check that. I'll let you know what I find out.