O2 sensor codes keep showing up

Rick Carter said:
I have replaced all o2 sensors ,took it to the dealer they thought it was the computer sent it to BBA back east they fix it send it to me I had it installed ,engine light still on the shop checks it an says computer call BBA it is under warranty send it back to them an they check it an find no problem with it they will overnight it back to me. Does any body have ideas I can tell Dave’s auto what to look for??? The Jeep dealer did a service bulletin 25-005-13 2005 Jeep Wrangler. Thanks Rick
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Sometimes it's the contacts in the multi-wire plugs going into the computer. That's what mine turned out to be. There is a few threads on the web on resoldering things but that's far deeper than I ever wanted to do. I 'fixed' it once by spraying some electrical contact clearner on the pins and plugs, followed by some other spray that enhances connections. Worked for a few 1000 miles. Unltimately went with FS1 refurbished computer, which has worked for over a year so far, and over some very rough trails
 
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shimaze said:
Having said that, what codes are you getting? As in what number? For example, I am getting the P0031, 37, 51, & 57 error codes. This is the heater circuit low for all four O2 sensors.

In closing, if your ONLY problem is the check engine light is ON, just be thankful it runs at all.
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P038, P058, P052, P032 are the codes.
And no, I can’t be thankful when I’m in NJ and can’t pass inspection with a CEL. I’ve been ticketed twice already for it and can’t continue to drive without the inspection sticker.
 
miss80five said:
P038, P058, P052, P032 are the codes.
And no, I can’t be thankful when I’m in NJ and can’t pass inspection with a CEL. I’ve been ticketed twice already for it and can’t continue to drive without the inspection sticker.
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Same codes i had. Check what cleaning the pins At the connection to the computer will do.
 
bluejeep said:
Same codes i had. Check what cleaning the pins At the connection to the computer will do.
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I cleaned the G105, didn’t do anything.
I sprayed the PCM connectors and it was good and CEL went off for 20 miles. Then came back on with all 4 codes again. Also, possibly important to note that the codes are coming up twice on the OBD II. Should I clean again? Wonder if I can rig it to go through inspection right after cleaning and after all I/M monitors have cycled through. I’ve been at this saga for over a year now.
 
here's a video of testing 02 heater. Its a jk, but the logic is the important part.
It should be easy to test the ground at the O2 sensor cable on the tj.

Edit: oops didn't check the ctrl+v
 
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Tighten the 4 pre cat bolts . Cold air triggers false readings . They have to be real snug and even. I just fixed an ‘05 this way.
 
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shimaze said:
miss80five,

Have you tried rewiring the fuse block? There is a TSB on it. The details are in the link. I did it to my Jeep and it wasn't too hard. It did not fix my problem, but I don't have the same exact problem you do. You may also have a bad computer?

Solution for 2005/06 TJ/LJ O2 Sensor Heater "not ready"
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Already changed PCM, all 4 O2 sensors, completed TSB, cleaned G105, bypassed grounding, and cleaned PCM contacts.
 
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miss80five said:
Already changed PCM, all 4 O2 sensors, completed TSB, cleaned G105, bypassed grounding, and cleaned PCM contacts.
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Is there anything else left to do? Sounds like you have done everything!

But just because you replaced the PCM does NOT mean that you replaced it with one that works! All to often, many people replace the PCM only to have it fail again. Many honest PCM rebuilders won't even touch a factory '05 & '06 Jeep Wrangler PCM. Some say don't send it to them if all four O2 sensor codes show.

Read the link below:

https://wranglertjforum.com/threads/05-06-pcm-issue-is-solved.21699/
 
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To test the the O2 sensors, I rigged up wire leads from an O2 sensor so I could check for voltage. Basically, you make a Y or T tap onto all 4 wires on the O2 sensor. This allows you to check for positive voltage to the O2 and also a ground to the block. You only need to do one and best to use an old sensor. I am getting no positive voltage to the O2 heaters on my Jeep.
 
shimaze said:
Is there anything else left to do? Sounds like you have done everything!

But just because you replaced the PCM does NOT mean that you replaced it with one that works! All to often, many people replace the PCM only to have it fail again. Many honest PCM rebuilders won't even touch a factory '05 & '06 Jeep Wrangler PCM. Some say don't send it to them if all four O2 sensor codes show.

Read the link below:

https://wranglertjforum.com/threads/05-06-pcm-issue-is-solved.21699/
Click to expand...

Ah yes, forgot some. Also ohm-metered all grounds, all four O2s, and therm tested the precats and cat.
 
Going thru a similar situation with my son's F150 right now. Been dealing with multiple O2 codes on each bank,(8cyl)
Engine runs like a swiss watch and we can rev it up nicely, we've been working on this for 3 weeks now and managed to get rid of the misfire but still had a power loss and there was clearly a rich mixture issue. The F150 have exhaust manifold issues so we pulled the engine and replaced both manifolds and extracted a handful of broken studs. After which the codes were all O2 sensors. After hitting a brick wall I had him take it in for a diagnostic and it came back with an issue with clogged cats. New cats being delivered Tuesday so hopefully that will resolve the issue. I had a cat go bad on a Toyota and it glowed red and killed any performance but not so this time, my brain did not even have cats in the thought process.
 
Do you know someone local that would willing to let you swap PCMs? I would be interested to know if the problem stayed with the Jeep or followed the PCM? Though I am not sure my idea is even possible?

https://rover.ebay.com/rover/1/711-...0001&campid=5337789113&icep_item=192032153301
Read the first few sentences in the tech notes. I spoke to this guy over the phone, He said the outlook for '05 & '06 PCMs is very dim. Mark Cantrell won't even accept these PCMs anymore. This eBay listing is what makes me think your PCM is still bad, even though you replaced it. That is why I purchased a NON '05/'06 PCM to run my '05 Wrangler
 
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shimaze said:
Do you know someone local that would willing to let you swap PCMs? I would be interested to know if the problem stayed with the Jeep or followed the PCM? Though I am not sure my idea is even possible?

https://rover.ebay.com/rover/1/711-...0001&campid=5337789113&icep_item=192032153301
Read the first few sentences in the tech notes. I spoke to this guy over the phone, He said the outlook for '05 & '06 PCMs is very dim. Mark Cantrell won't even accept these PCMs anymore. This eBay listing is what makes me think your PCM is still bad, even though you replaced it. That is why I purchased a NON '05/'06 PCM to run my '05 Wrangler
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The only good replacement PCMs for 05/06 Wranglers I'm aware of are now available from wranglerfix.com. They also figured out how to fix the programming errors that cause issues for the 42RLE automatic in those two years.
 
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This site contains affiliate links for which Jeep Wrangler TJ Forum may be compensated.
It sounds like the pcm. The OEM pcm will throw many false sensor codes, Tranny overheat, etc.

Anyone (anyone) peddling a repair on these particular pcms is selling you a pig in a poke.

Repairs on this is like fixing Humpty-Dumpty or placing a Band-Aid where you need a tourniquet.

My number is 866-888-7710 if you’d like to discuss.

Thanks,

Mark Cantrell
 
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