P0052 towing a trailer EUREKA

[1515art]

The Jeeps been running great, so I hooked up my trailer to take it to DMV for its vehicle inspection to complete the title registration. 2 miles into my journey I get a check engine light P0052. I pull over grab my OBD2 scanner it reads P0058 O2 sensor 2/1 hearer circuit high, looking this up it says cylinder bank opposite cylinder 1 O2 sensor after pre cat higher than expected voltage. Try to clear the code and it will not clear, drive home and put the trailer away, clear the code and go for a test drive and the Jeep runs great no check engine light no codes? Only thing different is I’m not connected to the trailers electric system and obviously I’m not towing the trailer. The couple times I did tow the trailer before the new transmission, driveshafts and muffler I had no problems and don’t really see how any of those are related? The one emission circuit that has never closed is the HTR and again not sure if that is related at all, I believe there is some service bulletin regarding the HTR not clearing but haven’t gotten into that yet, I’d passed smog inspection already.

All 4 O2 sensors were replaced 2 years ago with factory units when I replaced the pre cats and I’m stumped, could this be extra fuel pumping unburned being picked up by the bank 2 sensor 1 from the extra load of the trailer? And if so what would I do to correct this?

 

[1515art]

Graphing the live data with out the trailer attached it looks like 3 bad o2 sensors if I’m reading it correctly? I believe the graph is supposed to switch evenly up and down reading the voltage only o2s b2/s1 shows that pattern, the others look unusual and uneven at this point I think it needs 4 new o2 sensors would be best?

 

[1515art]

So I just got a check engine light without the trailer or it’s electric system connected to the Tj and think I can rule that out the trailer as a factor other than adding enough additional load to trigger this DTC. With at least 3 sensors displaying an irregular graph ill need to rule out a common ground, locate and inspect the grounds before swapping the 4 o2 sensors. The heaters for the sensors heat to somewhere around 750* or a little higher until hot exhaust gasses reach operating temperatures somewhere around 900*, is it possible the sensors could have been damaged when the old engine severely overheated?

 

[1515art]

Figuring I’d start by changing all the O2 sensors with my new set and keeping the old one for backup in case they were not the issue I started with B2 S2 and reaching up over the bell housing encountered the main engine strap dangling free near its home on the exhaust manifold stud, after a trip to Ace hardware for a handful of different sizes nuts and thread pitch the engine is now grounded.

Far from declaring success the DTC I had cured, a very short test drive with the engine main ground strap connected to the engine it feels if I’m not fooling myself like a different engine, better throttle response and more power the STFT’s spending less time in the negative numbers allowing more fuel to the injectors and resulting improved acceleration. Longer test drive tonight to see if the check engine light returns and if so what code shows, my air charge temp sensor also finally arrived at the dealer parts counter after a month so I changed that as well, this could be the source of better engine performance the new sensor reading ambient temperature at start-up versus the old one reading somewhere around 40* higher at start-up. Hopefully better fuel economy the last tank a measly 11.4 mpg.

tomorrow I’ll trace out the o2 heater wiring and change the remaining 3 O2 sensors.

 

[1515art]

I’m not sure what to make of this yet, possibly the tuning I had done corrupted the data on the @Wranglerfix PCM?


I have recorded the O2 live data graph for all o2 sensors in three different configurations, the first picture shows the 4 sensors as I started, the second picture is with the engine ground strap connected and all new NGK sensors, the third picture is ground strap connected all new NGK 4 sensors with my old factory PCM. I should have my new PCM on Monday and will repeat this again then with the new PCM. I have not found any other wiring issues or grounds missing yet, or tested the connection from the PCM for continuity.

 

[Chris]

Have you ran any of this by Mark (@Wranglerfix)?

I know he's tied up with some family stuff right now, but when he gets back into the groove of things, it would be interesting to hear what he has to say.

 

[1515art]

Have you ran any of this by Mark (@Wranglerfix)?

I know he's tied up with some family stuff right now, but when he gets back into the groove of things, it would be interesting to hear what he has to say.

I’ve been talking to him the last couple days, I ordered a second PCM just to have on hand and I might need it sooner than I thought it’s possible I corrupted the programming on the first one taking it to the Tuner. I don’t think , or don’t remember seeing the warning back when I bought the first one. I also sent him the comparison screen shot. I think the O2 sensors are ok, could be the PCM but I need to check against a new one the old factory PCM isn’t a very good baseline, after trying the new PCM I’ll check continuity and voltage at the PCM terminals, I guess it’s possible when it was dumping fuel a few tanks could have plugged the two 2 year old precats. There could be more things not connected or missing when the shop dropped in the engine I have taken care and lost count of a lot of things so far that make me scratch my head, I don’t know but eventually I’m going to run out of possibilities.

 

[Chris]

I’ve been talking to him the last couple days, I ordered a second PCM just to have on hand and I might need it sooner than I thought it’s possible I corrupted the programming on the first one taking it to the Tuner. I don’t think , or don’t remember seeing the warning back when I bought the first one. I also sent him the comparison screen shot. I think the O2 sensors are ok, could be the PCM but I need to check against a new one the old factory PCM isn’t a very good baseline, after trying the new PCM I’ll check continuity and voltage at the PCM terminals, I guess it’s possible when it was dumping fuel a few tanks could have plugged the two 2 year old precats. There could be more things not connected or missing when the shop dropped in the engine I have taken care and lost count of a lot of things so far that make me scratch my head, I don’t know but eventually I’m going to run out of possibilities.

Having used HPTuners numerous times on these PCMs, if you corrupt it, you should be able to just load the factory tune back on it, assuming you made a back-up before you started tuning. Do you know if that's the case? I always save a back-up before messing with it, just in case.

I would want a new PCM just to rule that out, so I agree with you there.

You could also do what I did and just disable the post cat O2 sensors completely. This will eliminate any codes they might throw, and it will run just fine. I did this so that I could remove all the cats, but you could do it just so that if the cats are messed up, the post-cat O2 sensors won't read anything and report it back to the PCM.

Just a thought

 

[1515art]

Having used HPTuners numerous times on these PCMs, if you corrupt it, you should be able to just load the factory tune back on it, assuming you made a back-up before you started tuning. Do you know if that's the case? I always save a back-up before messing with it, just in case.

I would want a new PCM just to rule that out, so I agree with you there.

You could also do what I did and just disable the post cat O2 sensors completely. This will eliminate any codes they might throw, and it will run just fine. I did this so that I could remove all the cats, but you could do it just so that if the cats are messed up, the post-cat O2 sensors won't read anything and report it back to the PCM.

Just a thought

Chris’s thank you fo the tips, what I’m learning and where I’ve been unfortunately are running at a different pace and there is no back-up, figured I’d talk to Mark and have him reflash it. The tuner I used was the only one I found advertised on google that worked on good old detroit’ish steel, most told me “you know we do...German , Japanese something other than Jeep. there is probably a dozen others I didn’t find, he‘s (Doc) a cool guy to talk to if approached in the right way but different. He always answered his phone like he’s avoiding a bill collector or a bounty Hunter, lol so I‘m mixed on what really happened except it did run better when I picked it up, but...

clark county has a smog check similar to California, will disabling the precats show up on the emission scanner? Is the procedure archived in your threads? And last question any chance the precats can let loose dumping into the main cat shutting you down, at the worst time usually, one of my objectives was to try and be as dependable as possible with a 16 year old Chrysler product. Now, what was the definition of insanity...something like fixing the same old Jeep the same old way and expecting it will be different, lol.

 

[Chris]

Chris’s thank you fo the tips, what I’m learning and where I’ve been unfortunately are running at a different pace and there is no back-up, figured I’d talk to Mark and have him reflash it. The tuner I used was the only one I found advertised on google that worked on good old detroit’ish steel, most told me “you know we do...German , Japanese something other than Jeep. there is probably a dozen others I didn’t find, he‘s (Doc) a cool guy to talk to if approached in the right way but different. He always answered his phone like he’s avoiding a bill collector or a bounty Hunter, lol so I‘m mixed on what really happened except it did run better when I picked it up, but...

clark county has a smog check similar to California, will disabling the precats show up on the emission scanner? Is the procedure archived in your threads? And last question any chance the precats can let loose dumping into the main cat shutting you down, at the worst time usually, one of my objectives was to try and be as dependable as possible with a 16 year old Chrysler product. Now, what was the definition of insanity...something like fixing the same old Jeep the same old way and expecting it will be different, lol.

If you need a tuner for these 4.0s, the only person I would trust is https://www.frptuning.com

Ryan is a former Chrysler employee who had a hand in helping the TJ engineers, and he has tuned my TJ for me as well. He knows these things inside and out and is definitely the go-to guy for 4.0 tuning.

You're not disabling the pre-cats, you're disabling the post-cat O2 sensors, which means they aren't reporting anything back to the PCM, which means it won't treat them as even being there. That will likely show up on their test, but I would say it may actually be worth seeing if you can skate by first. We don't have emissions here where we live, so it's a moot point for me. I do have the procedure outlined in one of my older threads where I review the HPTuners software. It's very, very easy to do.

The third cat (the one under the skid plate) has nothing to do with vehicle performance whatsoever. If it was clogged, it could affect performance, but what you're talking about seems highly, highly unlikely. I mean sure, it could happen, but I highly doubt it. Also, that'd third cat can be removed entirely if in doubt. I took mine out on every TJ I've owned, and it won't throw a single code as it has nothing to do with engine performance. You'll also be able to pass emissions just fine since it's not something that registers on their computers. That being said, you may just want to remove the third cat entirely just to rule it out. You'll also save some weight in the process, so it's a win-win.

I guess I'm lucky where we're at. I've managed to remove a lot of the emissions related bullshit. It's not that I think it's doing any harm, I just look at it as being more crap to go wrong, especially as these things tend to get older. If I can make my life easier by not having to chase down stupid problems like this, I look at that as a win.

 

[1515art]

Thanks Chris, I’m 2 years out from my next inspection so if in need to I may try disabling for now just so I can give my wallet a break, I’ve got a feeling from the two downstream sensors being code free up until now and it throwing codes at an accelerated rate it might have pumped enough fuel into the cats to have maxed out their ability to absorb much more unless somehow under the circumstances it will slowly over time play catch up? Think I’m dreaming.

 

[Wranglerfix]

I’m not sure what to make of this yet, possibly the tuning I had done corrupted the data on the @Wranglerfix PCM?


I have recorded the O2 live data graph for all o2 sensors in three different configurations, the first picture shows the 4 sensors as I started, the second picture is with the engine ground strap connected and all new NGK sensors, the third picture is ground strap connected all new NGK 4 sensors with my old factory PCM. I should have my new PCM on Monday and will repeat this again then with the new PCM. I have not found any other wiring issues or grounds missing yet, or tested the connection from the PCM for continuity.
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From what I have read, I think the most logical route is get the pcm back in me and I will check it in my Jeep. In the event the software is corrupt, I will reprogram it. If there is an 02 sensor issue with the pcm, it will get repaired. Rest assured we will get it figured out!

Now onto the past 168 hours of my life...

One kid gets a false positive for C-bug, one got dehydrated and took a trip to the hospital. One had a slight fender bender, my alternator and battery on my PT Cruiser took a on a busy road, USPS has 10 of my pcms MIA (blames corona) and south Florida has a hurricane coming!!

So, I will be on my kayak in a little while as the outer fringes start making their way to forget about and start anew!

Thanks for your patience in my responses.

Mark

 

[1515art]

Mark, absolutely no worries here so good you sons test was false positive, as a dad I can only imagine the stress with all this going on hope your son(s) are feeling better now. Add on the fender bender that’s a lot to deal with, hope at least the car crapping out didn’t happen in the middle of all this.

Back in April I was driving home after a full day hunting nuggets in the Arizona desert got myself dehydrated. I was driving home when it hit me, had time to pull the Jeep to the side of the road get out feeling like I was going to be sick made it to the back of the Jeep and dropped like a rock...couple nice ladies came to my rescue after I wome up.

The PCM’s will show up probably got side tracked with a batch of Trump ballots. There is no rush ill have the new one you sent me tomorrow and test the mail first with the package I promised, give you a chance to catch up before sending the other.

stay safe and sure glad I’m living in the desert never have to break out the kayak here, although I guess we get the occasional flash flood nothing like dealing with hurricanes, I left most of my natural disasters back in California.

 

[1515art]

Spell checker, wome (woke) had to look that one up; n., An endearing way to describe a chick or woman. Short form of woman. Similar to calling a male friend a dude. Hey, what's going on, wome?

 

[1515art]

This morning I was pretty convinced my precats were damaged from the fuel rich condition ive been experiencing and I guess they still could be hard to know if the old engine dumped any oil or water into them with the blown head gasket and fuel washing from the things I’ve fixed and what remains to be discovered.

Shoving my cheep Ryobi inspection scope into the hole for O2s B2/2 and looking up from the down stream end they don’t look bad like I expected, still chemically active is difficult to tell but not clogged or melted.

 

[1515art]

After months now fixing things (the shop) Vegas 4x4 f@)ked up putting my engine I in can finally say almost done, at least I now know what’s left. Following the clues I was pretty sure there was some small vacuum leak tricking the PCM into compensating a running the fuel ratio very rich, so the best solution test it with a smoke machine. Going on Amazon I found a unit that looked pretty good and had good reviews so I ordered this unit complete with all the plugs I might need.

price was around $300 it’s a complete tester and has an internal compressor.

hooking it into the throttle body I found leaks around and coming from under the valve cover most of the Allen screws were loose, there was some seepage from around the throttle shaft where it enters the throttle body, the big one and this caught me off guard I’ve only got maybe 1200 miles since the install...

the 2 front intake/exhaust manifold bolts were loose backed out a quarter inch, this has been to the tuner, muffler shop, transmission shop nobody caught it it wasn’t really obvious. And putting the smoke up the tail pipe it was leaking from 2 years ago when the muffler shop burned a small hole welding on the precats.

tightening everything as good as I can the intake/exhaust is still leaking a little it’s going to need a new gasket.

the live data and reports STFT still a bit high but in range, O2s booth looking good and the precats at 99.2%, pretty much everything right