Tennessee Red
- Thread starter gasiorv
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gasiorv
I'm a new world samurai, and a redneck nonetheless
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Because he is a redneck with a PhD.
gasiorv
I'm a new world samurai, and a redneck nonetheless
Original poster
Supporting Member
Ride of the Month Winner
Trying to figure out my misfire issue and I may have gotten a little wrapped up in the cam crank relearn because it is discussed so much. But with some research I found that the relearn is only applicable to the 05-06. There is a synch procedure for the 00-04 (mine is an 04), but there is no cam crank difference in the PCM or relearn required.
From this info that @sab posted a few years ago, it appears that the 2004 (JTEC+) and the 2005-06 (NGC) are different and that the 05-06 uses the relearn while my 04 would not have any type of relearn, it would just be a mechanical synch by turning the cam synchronizer until it was in range.
Sabs Info
I bought the Autel MK808S. I figured with the vehicles I have, plus my friends, plus helping my kids friends, etc... I would get some use out of it. I put it in my Amazon cart and a few days later they added a coupon so I got it for just over $350 (I think it was $383 with tax and everything).
Anyway, that thread from SAB also has a good video linked in it for doing the JTEC+ synch and I followed that procedure.
Here is the video
Mine was originally showing in range or it actually showed "in synch". My page was a little different than in the video but it had all the same parameters and mine had a Distributor setting of around 8 (not sure if that is degrees, I am assuming it is). I loosened the synchronizer and turned it until it was as close to zero as I could get it and then tightened it back up. It was jumping from approx -1 to +1 so that is pretty close to zero.
Unfortunately, since it was in range or in synch at the 8 deg, I am thinking that was not my issue, but perhaps the 8 deg is right on the edge of the in range and possibly if it goes outside that it could have had an affect on the injector timing?
I have recently replaced: CMP (Napa), CPS (Mopar), reinstalled my original injectors (I had 4 hole injectors installed), and the Ignition rail. I haven't recently replaced my spark plugs (they are not that old), but since relatively cheap I will add that to my list to change in the near future. When it does misfire, the only codes I get are the actual misfire codes P0300-P0306 or I get a Loss of Cam or Crank Position sensor signal, so I am leaning towards possibly a bad wire in the harness(s) somewhere. I did a quick check and there is no rubbing or wear on the harnesses that I can see from the outside so it is going to be a slow tedious inspection. After that, I have mechanical? One thing that lingers in my mind is that if I install the Wranglerfix PCM it seemed to misfire "quicker" than with my original OEM PCM.
I originally had no misfire issues, but a heat soak issue that would cause the Jeep to shut down when hot.
I replaced CPS, CMP, ignition rail (actually got a code for ignition rail during one of the heat soak shut downs). Still had heat soak issue.
Replaced the CPS again (because dumping water on the CPS to cool it down proved effective) and I replaced the PCM (just as a crutch) and the heat soak issue went away.
Right away the misfires started so I assumed it was the new PCM and I installed my old PCM. Misfires went away and it ran great. I had no heat soak issues and no misfires.
Exchanged the PCM that was causing misfires for another unit to have as a spare. When I received it I decided to install it just to ensure it was a good unit. Drove the jeep a few times on the road and no issues. Drove it on the road one last time before putting it on the trailer to go wheeling and I got a flashing CEL (indicating misfire) but it quickly went away and when I got home, no codes. I decided to put my original PCM back in since I knew it worked well during the last wheeling trip.
Old PCM-
Thurs night - a few misfires that I could feel and hear but no flashing CEL and no saved codes. There was a pending Interim Loss of Crank or Cam position sensor code in the memory.
Fri - Ran great all day, no misfires.
Sat - misfired in the morning, flashing CEL, Codes P0300, P0301, 0302, 0303, 0305, and 0306. Erased the codes and it ran great the rest of the day. No misfires and no flashing CEL, no codes were store (I checked that night).
Heat Soak issue first started in June 2024, very intermittent and only when working the jeep hard on an obstacle for a long time. I thought it was a vapor lock issue and never thought twice about it.
Replaced Cam Synchronizer in Aug 24 due to the bearings in the synchronizer going bad.
Next Heat Soak episode was in Sept and then had one in Nov (but there was a lot of wheeling in between). I thought it was a vapor lock issue and never thought twice about it.
Next Heat soak issue was in Moab in May 25 (with a lot of wheeling in between). However, at this time it was becoming more frequent.
No misfire issues during that time.
Changed CPS while in Moab and still had heat soak issue.
Returned from Moab and i replaced the CPS and the CMS and still had the heat soak issue.
Replaced the CPS and the PCM. Heat soak issue resolved but misfires started.
Installed old PCM and misfires went away for a whole weekend of wheeling.
Next wheeling trip, Misfires returned but intermittent.
Not asking for anyone to solve my issue, just typing it out so I can come back and review and remember some of the sequencing. Possibly, there is something in there that I forgot I changed (like I forgot I changed the CPS in Moab, when I returned from Moab, and then once again to solve the issue, so three CPS before it solved my heat soak issue). I also forgot that I changed the CMS when I returned from Moab, I removed a napa brand and installed a new napa brand and kept the old one as a spare, possibly the new CMS is causing the misfire? I also installed an ignition rail while trying to trouble shoot the heat soak and then the mis fires started. So possibly the rail?
From this info that @sab posted a few years ago, it appears that the 2004 (JTEC+) and the 2005-06 (NGC) are different and that the 05-06 uses the relearn while my 04 would not have any type of relearn, it would just be a mechanical synch by turning the cam synchronizer until it was in range.
Sabs Info
I bought the Autel MK808S. I figured with the vehicles I have, plus my friends, plus helping my kids friends, etc... I would get some use out of it. I put it in my Amazon cart and a few days later they added a coupon so I got it for just over $350 (I think it was $383 with tax and everything).
Anyway, that thread from SAB also has a good video linked in it for doing the JTEC+ synch and I followed that procedure.
Here is the video
Mine was originally showing in range or it actually showed "in synch". My page was a little different than in the video but it had all the same parameters and mine had a Distributor setting of around 8 (not sure if that is degrees, I am assuming it is). I loosened the synchronizer and turned it until it was as close to zero as I could get it and then tightened it back up. It was jumping from approx -1 to +1 so that is pretty close to zero.
Unfortunately, since it was in range or in synch at the 8 deg, I am thinking that was not my issue, but perhaps the 8 deg is right on the edge of the in range and possibly if it goes outside that it could have had an affect on the injector timing?
I have recently replaced: CMP (Napa), CPS (Mopar), reinstalled my original injectors (I had 4 hole injectors installed), and the Ignition rail. I haven't recently replaced my spark plugs (they are not that old), but since relatively cheap I will add that to my list to change in the near future. When it does misfire, the only codes I get are the actual misfire codes P0300-P0306 or I get a Loss of Cam or Crank Position sensor signal, so I am leaning towards possibly a bad wire in the harness(s) somewhere. I did a quick check and there is no rubbing or wear on the harnesses that I can see from the outside so it is going to be a slow tedious inspection. After that, I have mechanical? One thing that lingers in my mind is that if I install the Wranglerfix PCM it seemed to misfire "quicker" than with my original OEM PCM.
I originally had no misfire issues, but a heat soak issue that would cause the Jeep to shut down when hot.
I replaced CPS, CMP, ignition rail (actually got a code for ignition rail during one of the heat soak shut downs). Still had heat soak issue.
Replaced the CPS again (because dumping water on the CPS to cool it down proved effective) and I replaced the PCM (just as a crutch) and the heat soak issue went away.
Right away the misfires started so I assumed it was the new PCM and I installed my old PCM. Misfires went away and it ran great. I had no heat soak issues and no misfires.
Exchanged the PCM that was causing misfires for another unit to have as a spare. When I received it I decided to install it just to ensure it was a good unit. Drove the jeep a few times on the road and no issues. Drove it on the road one last time before putting it on the trailer to go wheeling and I got a flashing CEL (indicating misfire) but it quickly went away and when I got home, no codes. I decided to put my original PCM back in since I knew it worked well during the last wheeling trip.
Old PCM-
Thurs night - a few misfires that I could feel and hear but no flashing CEL and no saved codes. There was a pending Interim Loss of Crank or Cam position sensor code in the memory.
Fri - Ran great all day, no misfires.
Sat - misfired in the morning, flashing CEL, Codes P0300, P0301, 0302, 0303, 0305, and 0306. Erased the codes and it ran great the rest of the day. No misfires and no flashing CEL, no codes were store (I checked that night).
Heat Soak issue first started in June 2024, very intermittent and only when working the jeep hard on an obstacle for a long time. I thought it was a vapor lock issue and never thought twice about it.
Replaced Cam Synchronizer in Aug 24 due to the bearings in the synchronizer going bad.
Next Heat Soak episode was in Sept and then had one in Nov (but there was a lot of wheeling in between). I thought it was a vapor lock issue and never thought twice about it.
Next Heat soak issue was in Moab in May 25 (with a lot of wheeling in between). However, at this time it was becoming more frequent.
No misfire issues during that time.
Changed CPS while in Moab and still had heat soak issue.
Returned from Moab and i replaced the CPS and the CMS and still had the heat soak issue.
Replaced the CPS and the PCM. Heat soak issue resolved but misfires started.
Installed old PCM and misfires went away for a whole weekend of wheeling.
Next wheeling trip, Misfires returned but intermittent.
Not asking for anyone to solve my issue, just typing it out so I can come back and review and remember some of the sequencing. Possibly, there is something in there that I forgot I changed (like I forgot I changed the CPS in Moab, when I returned from Moab, and then once again to solve the issue, so three CPS before it solved my heat soak issue). I also forgot that I changed the CMS when I returned from Moab, I removed a napa brand and installed a new napa brand and kept the old one as a spare, possibly the new CMS is causing the misfire? I also installed an ignition rail while trying to trouble shoot the heat soak and then the mis fires started. So possibly the rail?
I went through some similar issues with my '04 and know how frustrating it can be. In my case, I had to get the signal sync set to exactly zero (It took me 3 trys to get it correct) and it ran like it should. I've still got a heat soak problem, which I've had on other '03 and '04 Wranglers, but it only happens when it's hot and the Jeep is shut off, then started up again quickly. Since you replaced the camshaft position sensor, just verify that the plug is facing directly to the firewall. If it's one tooth off it will run fine sometimes, while generating misfire codes other times.
When you say "ignition rail" I'm assuming you're talking about the coil pack. If so, I got a bad one once where one of the plugs was missing a spring that goes inside it. This was a rare problem and highly likely not your issue. I'd go back to the stock coil pack, unless that was a known issue, so you not introducing too many variables for troubleshooting.
When you say "ignition rail" I'm assuming you're talking about the coil pack. If so, I got a bad one once where one of the plugs was missing a spring that goes inside it. This was a rare problem and highly likely not your issue. I'd go back to the stock coil pack, unless that was a known issue, so you not introducing too many variables for troubleshooting.
gasiorv:
Sounds like you've ruled out cam/crank position sensor synchronization, and with all the sensor changing you did, I think you can rule out sensors. It would seem to be an incredible coincidence to have so many bad sensors. The only suggestion I can give is to review the "Possible Causes" section and the troubleshooting section that follows in the Powertrain Diagnostic Procedures Manual for any codes you get. Although there's no 2004 Powertrain Diagnostic Procedures Manual in the resources section, there is one for 2002, and it's identical. Good luck!
Sounds like you've ruled out cam/crank position sensor synchronization, and with all the sensor changing you did, I think you can rule out sensors. It would seem to be an incredible coincidence to have so many bad sensors. The only suggestion I can give is to review the "Possible Causes" section and the troubleshooting section that follows in the Powertrain Diagnostic Procedures Manual for any codes you get. Although there's no 2004 Powertrain Diagnostic Procedures Manual in the resources section, there is one for 2002, and it's identical. Good luck!
gasiorv
I'm a new world samurai, and a redneck nonetheless
Original poster
Supporting Member
Ride of the Month Winner
Here is some footage of Jeff at Windrock.
Walden's Ridge Gatekeeper. Video doesn't do this section justice because there is a huge drop off on the passenger side and the vehicle is always leaning towards that drop off. As the driver, it is a a real mind freak. As the driver once you pop up on top of the ridge you are staring at a huge drop off, it is approx 1000' with no trees or anything to stop you from going over. Jeff normally uses the power of that rig, but as you can see in this video he is real tame and cautious, it is a real mind freak!
This fun rock section is about 3/4 of the way through Walden Ridge. It is a fun little section. Here you will see Jeff in his normal mindset using the throttle!
After doing a super tight Trail 49 where Jeff's rig was a little on the big side for some of the tight squeezes between some of the trees, he was ready to stretch out a little on Trail 90. Video doesn't do it justice on how high that Driver's side front wheel was in the air, haha!
Walden's Ridge Gatekeeper. Video doesn't do this section justice because there is a huge drop off on the passenger side and the vehicle is always leaning towards that drop off. As the driver, it is a a real mind freak. As the driver once you pop up on top of the ridge you are staring at a huge drop off, it is approx 1000' with no trees or anything to stop you from going over. Jeff normally uses the power of that rig, but as you can see in this video he is real tame and cautious, it is a real mind freak!
This fun rock section is about 3/4 of the way through Walden Ridge. It is a fun little section. Here you will see Jeff in his normal mindset using the throttle!
After doing a super tight Trail 49 where Jeff's rig was a little on the big side for some of the tight squeezes between some of the trees, he was ready to stretch out a little on Trail 90. Video doesn't do it justice on how high that Driver's side front wheel was in the air, haha!
My wife joined me at SMORR in Missouri for her first big trip and now she's hooked! We have a trip planned for Hot Springs and Sand Hollow this winter.
gasiorv
I'm a new world samurai, and a redneck nonetheless
Original poster
Supporting Member
Ride of the Month Winner
I was pointing with my thumb to go up hill and yelling to go down hill, haha!
Well, my meme force is weak. It was supposed to be an animated gif:
https://y.yarn.co/798b15f9-b349-4325-bd39-4f3581edda69_text.gif
https://y.yarn.co/798b15f9-b349-4325-bd39-4f3581edda69_text.gif
gasiorv
I'm a new world samurai, and a redneck nonetheless
Original poster
Supporting Member
Ride of the Month Winner
I replaced the coil rail and the spark plugs and the jeep definitely ran better, it is like it now "fires up with half a key turn and just wants to go", of course that is just a "feeling" and not a diagnostic. Anyway, drove it one day and no misfires. Drove it the second day and the check engine light starting flashing intermittently during my drive, I was doing 35mph in 4th gear just cruising, not on the throttle at all. . I could not feel any misfires, I just saw the CEL flashing. It would flash a few times and then quit and then flash a few times and quit.......... When I got home it had a P0300 pending. That was the only code Random Mis-Fire.
This morning (you got to work at night and early morning in this Memphis heat!!). I checked the wire harnesses that run to PCM, to the Cam Pos Sensor and to the Crank Pos Sensor, as well as the one that runs to the injectors and I saw no wear. I then hooked up my scanner and watched the mis-fire count and I had zero at start up, I let the engine warm up and had zero. I then started shaking and pinching the harnesses, watching the misfire count and none. I then used carb cleaner to spray around the throttle body, intake, vacuum lines, etc... and nothing. All runs good.
I was starting to think back to wheeling and I remembered that on the Windrock Trip on Thurs night when it first mis-fired it was also having a high idle. It was idling around 900-1000 RPMs in lieu of around the 600 RPMs that it normally did. It only did this for a short period of time and seemed to occur prior to the misfires starting. It never did it again the entire weekend or since then. Based on this, I again checked for vacuum leaks, but none could be found. Again, just capturing info for future reference, not sure if it means anything.
Scanner and TPS question for anyone who may know? How does the scanner bump up the RPMs with a cable throttle? My understanding is that the TPS only provides a signal to the PCM. So how does it bump up the RPMs? When I did the cam synch procedure, it definitely bumps up the RPMs to 1000 RPM during the test, so I know it does it. But when I went into the scanner and selected to actuate the RPMs to 2000 RPMs, I could here a slight change in RPM but it did not take it to 2000 RPM and it actually went down slightly? Weird?
This morning (you got to work at night and early morning in this Memphis heat!!). I checked the wire harnesses that run to PCM, to the Cam Pos Sensor and to the Crank Pos Sensor, as well as the one that runs to the injectors and I saw no wear. I then hooked up my scanner and watched the mis-fire count and I had zero at start up, I let the engine warm up and had zero. I then started shaking and pinching the harnesses, watching the misfire count and none. I then used carb cleaner to spray around the throttle body, intake, vacuum lines, etc... and nothing. All runs good.
I was starting to think back to wheeling and I remembered that on the Windrock Trip on Thurs night when it first mis-fired it was also having a high idle. It was idling around 900-1000 RPMs in lieu of around the 600 RPMs that it normally did. It only did this for a short period of time and seemed to occur prior to the misfires starting. It never did it again the entire weekend or since then. Based on this, I again checked for vacuum leaks, but none could be found. Again, just capturing info for future reference, not sure if it means anything.
Scanner and TPS question for anyone who may know? How does the scanner bump up the RPMs with a cable throttle? My understanding is that the TPS only provides a signal to the PCM. So how does it bump up the RPMs? When I did the cam synch procedure, it definitely bumps up the RPMs to 1000 RPM during the test, so I know it does it. But when I went into the scanner and selected to actuate the RPMs to 2000 RPMs, I could here a slight change in RPM but it did not take it to 2000 RPM and it actually went down slightly? Weird?
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