From what I understand, the part they use is different and it’s a bit more expensive and harder to come by.
They cannot be flashed.
05-06 PCM issue is solved
- Thread starter Wranglerfix
- Start date
From what I understand, the part they use is different and it’s a bit more expensive and harder to come by.
They cannot be flashed.
Alright, so progress! The Jeep will run again and I took it on a weekend trip to gain confidence before a much bigger and involved trip in September. So far there are no signs of issues new or old, I’m hoping this continues for an easy wheel with my 5yro tomorrow.
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I finally get a chance to post my experience with Mark at Wranglerfix. Short story, it was great.
It wasn't until after I bought my 2005 LJ, that I read about PCM problems. After two years of ownership, and no issues, I was feeling pretty good about my PCM, until last week.
I frequently get a CEL from a "small evap system leak". I reset the CEL and can go weeks to months without it returning. This summer, I've been driving with the CEL for awhile. I also started to notice an occasion hard 1-2 shift. Last week, I plugged in my code reader to reset the CEL, I got two completely different error codes. Both were PCM related.
I contacted Mark through his website, and he replied quickly. I ordered a new PCM last weekend, and it arrived today. A 10 minute install and no CEL from my test ride around the block. No CEL could have also been from disconnecting the battery. My initial impression is my problem is fixed. I will monitor and update this thread if anything changes, but so far, I'm a happy camper.
It wasn't until after I bought my 2005 LJ, that I read about PCM problems. After two years of ownership, and no issues, I was feeling pretty good about my PCM, until last week.
I frequently get a CEL from a "small evap system leak". I reset the CEL and can go weeks to months without it returning. This summer, I've been driving with the CEL for awhile. I also started to notice an occasion hard 1-2 shift. Last week, I plugged in my code reader to reset the CEL, I got two completely different error codes. Both were PCM related.
I contacted Mark through his website, and he replied quickly. I ordered a new PCM last weekend, and it arrived today. A 10 minute install and no CEL from my test ride around the block. No CEL could have also been from disconnecting the battery. My initial impression is my problem is fixed. I will monitor and update this thread if anything changes, but so far, I'm a happy camper.
I want to share my initial experience with ny new PCM. I was only expecting the CEL to go away, but I was pleasantly surprised that my jeep performed better.
After my previous post, I took a short 50 mile drive. My route was through the "mountains" of PA. Normally when I drive this route, I switch the OD off. I was preoccupied tonight and forgot. The first thing I noticed was that I could accelerate uphill. My initial thought was the OD was off, but I looked at my tach, and I was about 2100 RPM. I switched off the OD and the RPM jumped to 2800. I switched the OD back off and continued my drive.
At the next stop sign, with damp roads, I pulled out quickly. To my amazement, I spuns my tires a little. I've never done this before. The more I drove, the more I liked what the new PCM was doing.
Mark called me tonight as a follow up, after I emailed him to let him know my PCM arrived. I asked Mark if I was imagining things about improved performance. He said I wasn't imagining things. It's not so much that the PCM boosts power, but for my jeep, the old PCM probably wasn't doing a good job processing inputs. The new PCM processes input from the O2 sensors and other things better than my old PCM. My jeep now runs as it was supposed to.
After my previous post, I took a short 50 mile drive. My route was through the "mountains" of PA. Normally when I drive this route, I switch the OD off. I was preoccupied tonight and forgot. The first thing I noticed was that I could accelerate uphill. My initial thought was the OD was off, but I looked at my tach, and I was about 2100 RPM. I switched off the OD and the RPM jumped to 2800. I switched the OD back off and continued my drive.
At the next stop sign, with damp roads, I pulled out quickly. To my amazement, I spuns my tires a little. I've never done this before. The more I drove, the more I liked what the new PCM was doing.
Mark called me tonight as a follow up, after I emailed him to let him know my PCM arrived. I asked Mark if I was imagining things about improved performance. He said I wasn't imagining things. It's not so much that the PCM boosts power, but for my jeep, the old PCM probably wasn't doing a good job processing inputs. The new PCM processes input from the O2 sensors and other things better than my old PCM. My jeep now runs as it was supposed to.
Drewbie
New Member
Hi everyone,
Just wanting to share my situation and outcome with everyone. Roughly 4 months ago I had my 05 TJ with 6 speed manual and 4.0 liter stall on me after I fueled up one hot afternoon. It took nearly 10 restarts to get it home only quarter mile away. First code it threw was the crank sensor code, later followed by the cam sensor, kind of made sense due to its symptoms. Hard to start, gauges going crazy, random stalling. I checked for voltage on the harness and looked for shorts and damaged wires, all tested/looked good so I replaced the crank sensor with a Mopar sensor and hoped for the best. Took it for a test drive and shortly after it started stalling again, would not restart, this time the engine light would come and go, unplugging the sensors didn't help, scanner could not connect to computer to retrieve codes. Towed it home and continued trouble shooting. Letting it idle in my driveway as to not get stuck somewhere along the road. After about 10 minutes idling it started dying. Finally got a code for all three coils and every O2 sensor heater. 38, 32, 58 and 52. This has been after roughly 2 months of me trouble shooting. I found on this forum it may be the pcm. I called Mark at wrangler fix and he felt pretty confident that the pcm was my problem as well. Me trying to save a buck I sent the pcm to a place close to me in Illinois for repair, they happily took $130 to return me a pcm that still didn't work. I went ahead and ordered from wrangler fix, I received it quicker than I expected and it was an easy plug and play. Currently I have 100 miles on the pcm from wrangler fix and I have not seen any sign of a problem. No stalling, no engine light and Jeep feels more peppy, could it have been that simple? I will come here and update when I get some more miles on it. I am hopeful it is fixed but it may be a while before I am confident in my TJ again. Mark has been great throughout also, he has personally called to check on it and make sure everything was good.
Just wanting to share my situation and outcome with everyone. Roughly 4 months ago I had my 05 TJ with 6 speed manual and 4.0 liter stall on me after I fueled up one hot afternoon. It took nearly 10 restarts to get it home only quarter mile away. First code it threw was the crank sensor code, later followed by the cam sensor, kind of made sense due to its symptoms. Hard to start, gauges going crazy, random stalling. I checked for voltage on the harness and looked for shorts and damaged wires, all tested/looked good so I replaced the crank sensor with a Mopar sensor and hoped for the best. Took it for a test drive and shortly after it started stalling again, would not restart, this time the engine light would come and go, unplugging the sensors didn't help, scanner could not connect to computer to retrieve codes. Towed it home and continued trouble shooting. Letting it idle in my driveway as to not get stuck somewhere along the road. After about 10 minutes idling it started dying. Finally got a code for all three coils and every O2 sensor heater. 38, 32, 58 and 52. This has been after roughly 2 months of me trouble shooting. I found on this forum it may be the pcm. I called Mark at wrangler fix and he felt pretty confident that the pcm was my problem as well. Me trying to save a buck I sent the pcm to a place close to me in Illinois for repair, they happily took $130 to return me a pcm that still didn't work. I went ahead and ordered from wrangler fix, I received it quicker than I expected and it was an easy plug and play. Currently I have 100 miles on the pcm from wrangler fix and I have not seen any sign of a problem. No stalling, no engine light and Jeep feels more peppy, could it have been that simple? I will come here and update when I get some more miles on it. I am hopeful it is fixed but it may be a while before I am confident in my TJ again. Mark has been great throughout also, he has personally called to check on it and make sure everything was good.
May I ask why you replaced yours? I also have a manual 05.. And all at once I got O2 heater circuit voltage low codes... P 0031, P 0037, P 0051 & P 0057
I've replaced the upstream sensors recently due to codes a while ago which resolved that issue. I am going to test ohms and voltages on the O2 sensors soon... As well as the common #105 ground. But want to know if my PCM is dead.. How can I 100% confirm that it's my PCM?
James Brewer
TJ Enthusiast
James Brewer
TJ Enthusiast
I went through about a month of replacing 02 sensors..it was not the sensors, drop your manifold pipe get a flash and inspect your cats. They should have very uniformed small holes as they are porous. If they are cracked broken or have large holes and chunks missing they will not hold enough heat and trip the sensors.
Thanks. I'm going to get the sensors out and run volt meter tests on sensor wire as well as heater circuit wire just to be sure they are okay or not.
What is weird is that when I unplug the 4 sensors the codes go away 1 at a time... Does that make sense? Would the PCM just ditch the codes it sensors get unplugged?
Thank you for the posts. I have ha my 06 TJ pcm rebuilt twice only for it to work for 2 weeks. I will be trying wrangler fix next.
James Brewer
TJ Enthusiast
Ya, my 06 does this from time to time when i happen to spin the tires a bit like pulling out off a dirt lot or lose gravel...Boom code and in limp mode, I can shift to neutral, turn the engine off and restart while rolling put in gear and all is good....first make sure you are at or really above the full line on your transmission fluid.
I have an aftermarket radiator and thus I had used some hose and clamps to connect the transmission line to the cooler at the bottom of radiator.....I have since replaced the quick connector at the bottom of radiator and installed new Transmission lines and its been about 45 days since with no issues..
Now also I had ordered and install a new ECM/TCM from Wrangler fix, within 5 miles of driving it threw a p0016 code and I sent it back to WranglerFix..So I am back on my stock ECM and all is good....(UMM Mark if your reading this, when will I get the ECM backCOUGH COUGH)
James Brewer
TJ Enthusiast
I get the same, it happens if I spin the tires pulling off the dirty drive way or gravel road...its not limp mode but it will not shift gears and a p0700 code. I shift to neutral turn off ignition, restart, shift back to drive all normal again. Hoping new pcm fixes this.
Ljeepo
New Member
Can I call you guys tomorrow ? I’m having issues with my 05 but I’m not sure if a pcm is what I need
James Brewer
TJ Enthusiast
Update...revieved second ECU from Wranglerfix..installed and had p52 code immediately...tells me the first ECU was faulty. Remember it gave me a p16 code after driving less than 5 miles. So different code this time, p52 is O2 sensor bank 1, bad fuse or...ya, bad ECU...anyway once again back on my stock ECU...sent wranglerfix's ECU back to them on my dime and waiting for a 3rd one I guess...not looking good as WranglerFix is 0 for 2.
James Brewer
TJ Enthusiast
You better test it...mark at wrangler fix is good about customer service but so far he's 0 an 2 with me on his ECUs
A completely different pcm is being tested and shipped today, James. I sent you and email and test with the tracking information.
Please let us know when you get this one installed.
Mark
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