O2 sensor code P0157


lulzpwndyah

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I have a 2005 Wrangler SE with the 4.0

I have 2 PCM one OEM and one @Wranglerfix... The OEM has 4 O2 sensor codes that won't go away and this is a problem with the PCM... but I don't have P0157.... when I plug in the wranglerfix pcm I only get code P0157. I don't know why i'm getting the code I have 4 new O2 sensors installed the proper NGK ones. I also have 2 new precats so I know that's not the problem. All of these parts have less than 2k miles. Does anyone have any thoughts? I've looked at the wiring and the wiring seems fine, i've had 1 mechanic look over the wiring and he said it was fine.

Anyone else have any thoughts? I couldn't find too much online other than what i've already listed here.
 
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lulzpwndyah

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On my drive home today I decided to check the CEL for the heck of it and found out I had another code
So now I have P0157 and P0057
Both O2 sensor codes for the same sensor I believe.
 

Chris

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If you have a replacement PCM from @Wranglerfix, that rules out the PCM.

Having replace all 4 O2 sensors with the proper NGK sensors, that should rule them out as well.

The only things that this possibly leaves in my mind would be failing catalytic convertors (which would usually have other symptoms) or a break in the wiring somewhere. In fact, I would honestly bet it's one of those two issues.

Sometimes the breaks in the wiring can be very, very tricky to track down.
 
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lulzpwndyah

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I’m going to have my best friend whose an electrician come out and help me because the cats are new so it only leaves the wiring to be faulty and I personally have not been able to find the problem.
I’ll check it out this weekend and update.
 
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lulzpwndyah

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@lulzpwndyah one of the possibilities on p0057 leads back to the pcm. Please keep me updated...if necessary I will get the pcm back into get tested.

I will get back to you soon after the testing of the cables. I would definitely appreciate that it just helps knowing I can get all bases covered. I just want the rare unicorn with no check engine lights haha
 
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Wranglerfix

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Check your harnesses very well. The poor guy chased wires for weeks. Two pieces of electrical tape and he’s still running strong.

38262A86-E563-4D8F-9275-D77C11BF9AD5.jpeg
 
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