When purchased prox 6 weeks ago, my 2005 Rubicon had budget no-name (Made in Cambodia?) 35x12.5R15 tires recently installed by the short-term prior owner. With desire for better overall match to the 42RLE trans and so-stated 5.13 gearing (subsequently confirmed below) and while also not trusting those otherwise decent looking tires sidewall construction off-pavement, I replaced those with a full set of 5 - BFG M/T KM3 33x12.5R15. After that, I removed the old SuperLift speedometer calibrator which had a wonky selector toggle switch. As part of doing that revealed that the Speed Sensor cable harness connector had previously been damaged, with the protruding plastic pins on that male side connector broken off, not locking into the mating female connector with red latch tab. Significant difficulty separating suggested superglue or equivalent had been used to keep those halves connected. Attempts to temporarily tape together proved unsuccessful, with them pulling apart and losing contact with no speed signal subsequently sent to the PCM (2005-2006 with integrated TCM). I drove multiple trail miles with that becoming disconnected and then re-taped it at home for even more miles, despite the speedo error.
Our trail run yesterday was aborted just a few miles off-pavement when the CEL illuminated along with 42RLE "false neutrals" a few times. My OBDLink MX+ bluetooth dongle displayed P0344 "Cam Position Sensor" error on my phone app, so we called it quits and turned back. Fortunately, home is just 2 miles from end of pavement forest access, so I got back OK.
I recently purchased and installed a new WranglerFix PCM and also purchased (but not yet installed) a new Crown OPDA, so I reflected on what transpired and considered;
> 33" vs 35" tires affect PCM calculations, however unlikely related to that P0344 code. New PCM being the root cause likewise seemed unlikely.
> Replacing OPDA with attached Cam Position Sensor at that point seemed illogical, WRT mechanical function of the OPDA and the OEM CPS' considered overall reliability.
> The variable being possible effects of erroneous info sent to PCM (no Speed Sensor in play and/or 20% calculated speedo error vs GPS actual).
So last night, I installed the replacement new Speed Sensor (**) and routed the new SpeedoHealer unit (both purchased in advance). I disconnected the battery neg terminal overnight (prox 15 hours) to clear adaptive memory. Did that vs touching disconnected pos cable to neg terminal for several minutes as outlined elsewhere here. This morning, checked for any frayed harness wires but found none, reconnected the battery and used SpeedoHealer's app to quickly and easily recalibrate within .5 mph accuracy result on my 1st attempt.
This afternoon, we completed prox 70 miles off-pavement and pavement without repeat of P0344 or "false neutrals". My thinking last night seems was correct, i.e., don't add variables to confuse diagnostics, i.e., replacement of the OPDA / CPS sensor combo prematurely until more data was known. I now suspect that the PCM was totally "confused" by no speed or grossly incorrect speed signals, thus was attempting to control the 42RLE inconsistently. I'm open to contrary opinions on this aspect., but I'm "cautiously optimistic" the problem has been resolved.
(**) Having read here about sub-par Speed Sensor and Cam Position Sensor replacements, I returned the SMP PC659 sensor purchased on Amazon and paid more for one purchased on eBay from a seller whom stated it's an OEM New Venture Gear part they source directly from them. That version didn't appear much (if any) different from SMP's, however sourced from NVG was worth the additional cost to me. I was able to transfer the old o-ring over to the new sensor without damage.
Allstate Gear: Jeep Wrangler Rubicon NP241OR Transfer Case Speed Sensor, 45900
BTW, last week while draining both Dana 44 differentials and replacing with R-P gear oil and LubeLocker gaskets (as done with former 2000 TJ and current 2017 JK Rubicon), the front ring gear had conveniently stopped at a position which confirmed the stated 5.13 reduction. I'm unsure what the "Circle K" brand marking might be. If anyone knows, chime in...
Our trail run yesterday was aborted just a few miles off-pavement when the CEL illuminated along with 42RLE "false neutrals" a few times. My OBDLink MX+ bluetooth dongle displayed P0344 "Cam Position Sensor" error on my phone app, so we called it quits and turned back. Fortunately, home is just 2 miles from end of pavement forest access, so I got back OK.
I recently purchased and installed a new WranglerFix PCM and also purchased (but not yet installed) a new Crown OPDA, so I reflected on what transpired and considered;
> 33" vs 35" tires affect PCM calculations, however unlikely related to that P0344 code. New PCM being the root cause likewise seemed unlikely.
> Replacing OPDA with attached Cam Position Sensor at that point seemed illogical, WRT mechanical function of the OPDA and the OEM CPS' considered overall reliability.
> The variable being possible effects of erroneous info sent to PCM (no Speed Sensor in play and/or 20% calculated speedo error vs GPS actual).
So last night, I installed the replacement new Speed Sensor (**) and routed the new SpeedoHealer unit (both purchased in advance). I disconnected the battery neg terminal overnight (prox 15 hours) to clear adaptive memory. Did that vs touching disconnected pos cable to neg terminal for several minutes as outlined elsewhere here. This morning, checked for any frayed harness wires but found none, reconnected the battery and used SpeedoHealer's app to quickly and easily recalibrate within .5 mph accuracy result on my 1st attempt.
This afternoon, we completed prox 70 miles off-pavement and pavement without repeat of P0344 or "false neutrals". My thinking last night seems was correct, i.e., don't add variables to confuse diagnostics, i.e., replacement of the OPDA / CPS sensor combo prematurely until more data was known. I now suspect that the PCM was totally "confused" by no speed or grossly incorrect speed signals, thus was attempting to control the 42RLE inconsistently. I'm open to contrary opinions on this aspect., but I'm "cautiously optimistic" the problem has been resolved.
(**) Having read here about sub-par Speed Sensor and Cam Position Sensor replacements, I returned the SMP PC659 sensor purchased on Amazon and paid more for one purchased on eBay from a seller whom stated it's an OEM New Venture Gear part they source directly from them. That version didn't appear much (if any) different from SMP's, however sourced from NVG was worth the additional cost to me. I was able to transfer the old o-ring over to the new sensor without damage.
Allstate Gear: Jeep Wrangler Rubicon NP241OR Transfer Case Speed Sensor, 45900
BTW, last week while draining both Dana 44 differentials and replacing with R-P gear oil and LubeLocker gaskets (as done with former 2000 TJ and current 2017 JK Rubicon), the front ring gear had conveniently stopped at a position which confirmed the stated 5.13 reduction. I'm unsure what the "Circle K" brand marking might be. If anyone knows, chime in...
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