fr3dbilli3

ok so my CEL came on and the car was running fine until it wasn't. started with a light rough idle but the problem got worst. the computer gave me o2 sensor so we swapped it out. 2 weeks later boom CEL o2 sensor. swapped again. now we also replace the computer, still, o2 sensor CEL. what the heck is going on. someone help me. is the problem something that can be messing up the o2 sensor ?

doublechaz

Codes don't always mean that the sensor is bad. They just mean the computer can't understand something related to that code. E.g. an exhaust leak could let enough oxygen in to the exhaust to pin the O2 reading lean for a long enough time for the computer to set an O2 sensor related code.

There are many things that can break to set a code for any particular sensor. The code is just to get you started in the right direction. From there you have to gather your own data and use knowledge of the theory of operation of internal combustion engines to figure out what is acutally wrong.

We can help out with the knowledge part, but we can't get the data.

Since you've replaced the sensor many times and also the computer we can guess that those are not the problem and something else is causing this code. It was already stated in another thread that you should be checking for a wiring fault. Skipping that step and continuing to parts swap will just result in wasted money, wasted time, and frustration.

exasemech

When you get an O2 code, or a code related to any other component, that does not mean "this part it bad, replace it and the problem is solved". It means that there is some problem with the part OR the wiring associated with the part OR one of the connectors OR how the computer is communicating with the part. You need to look at the data your scan tool is giving you regarding the O2 sensor, this will help you narrow down the problem. I suspect a wiring/connector but you need to do your own diagnosis.

Edit :doublechaz types faster than I do...:-l

fr3dbilli3

hey guys sorry i posted this twice i didnt think this post went through andi guess i now opened my computer and listed it. with that being said im waiting on my test light and multimeter in the mail now to check the wiring harness that connects to the o2 sensor. appreciate you guys very much and i hope to diagnose this myself as it feels good to get things going especially because i bought this car with this sputter

awg

a crap brand O2 sensor will throw a code in next to no time

use a good quality, or even a used one and see if that makes a difference

(after following the good recomendations of previous posters)

Ralph77

That brings up the question that I usually ask.
What brand O2 sensor?

Dave51

How many O2 sensors you got? What is the specific code?

So PO changed it twice too?

That thing got an 0331 head?

Dave51

You can also get one of those freebie OBDII+ software apps and see what you sensors are doing. Might be cat time.

Typical O2 sensor graph:



That one's a sick sensor but you can also use it to figure out if you have a cat problem.

fr3dbilli3

swapped out twice. could be bad wiring but have to check

PO132

0331 head for sure

Dave51

The acquisition time of those apps is pretty slow so the graphs look kinda stupid but should be good enough to identify issues.

exasemech

To the OP

Given how many O2 sensors that have been put into that thing recently it's a little hard to believe they were all bad out of the box. Look at the sensor voltages you are getting on your scan tool; do they drop to zero-as in nothing? Or is there a voltage but the shift seems slow? If zero, another hint that maybe a wiring issue.
it is also possible something is contaminating the sensors. Need to be a lot of it to do it that fast but possible. Are you losing coolant that is showing up in the exhaust?

Note that I keep referring to "your" scan tool. If you don't have one run, don't walk, to a parts store and buy one: not a code reader but something that will give you live data. You can buy one for the price of an O2 sensor and if you are going to own a clapped out old vehicle you need one. Having a parts store read codes for you is not a solution.

ALSO reading all the various threads you have posted on this thing I realized it is a 2000 and you bought it in New Jersey. If it was originally sold in NJ it is likely a California version. (Check the emission label) They have 2 close coupled cats with an upstream and downstream O2 sensor on each...thats 4 total. The downstream sensors do nothing as far as the car running is concerned, they are for the OBD cat check

Do you have any idea which o2 sensors are showing bad? Again a scan tool will tell you. Which ones have been replaced?

bluejeep2001

disconnect both front or the one o2 sensor at the front connectors...computer now ignores o2 signals and goes to a preset standard calculation...if it smoothes out and runs better then you know there is nothing physically wrong but its a sensor/control issue

fr3dbilli3

can you check my newest post about a pinch hose and tell me if maybe thats whats causing this mess?

Very Red XJ

Check the wiring harness coming up from the O2 to the fuel rail wiring harness - Chryslers wire shielding often deuterates letting the wires ground out. Do this before you buy another O2 senser

exasemech

https://www.walkerproducts.com/o2-se...xygen-sensors/