Jeep Wrangler Forum banner

1 - 13 of 13 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1
2005 rubicon LJ with Eaton m90 supercharger. One year ago p0016 and maybe another 300 series code popped up. Replaced OPDA and cam sensor as the jeep was up there in miles anyway. Code and limp mode fixed.


fast forward to present day, I cant shake this p0344 code and limp mode. Weekends trouble shooting:

  • 4.9V to cam sensor
  • continuity in cam sensor ground through PCM
  • cam sensor signal output around 2V (micrometer only, not scoped)
  • continuity from cam sensor signal to PCM
  • continuity from cam sensor signal through secondary ECU (for fueling)
  • continuity in ground circuit from PCM to vehicle speed sensor
  • continuity in 5V power from PCM to vehicle speed sensor
  • visually inspected cam sensor harness, no apparent shorts in cam signal wire or 5V source wire.
  • shake test with harness and multimeter for previously listed (trying to find short or open)
  • verified cam sensor sync
  • aftermarket or OEM cam sensor does not make a difference
  • all continuity tests were with the sound setting. Solid even tone was generated for all
  • code tripped under light load, 120*F coolant temp.
Any ideas? I haven't checked the crank sensor, but only the ground circuit seems to go through that sensor and ground checks out. Open to suggestions as I don't know what else to do at this point. Jeep is two hours away so every time I go to troubleshoot its an event.



Thanks!
 

·
Registered
Joined
·
3,581 Posts
The aftermarket cam sensors are definitely problematic & for some time the ones from the dealers are no better. The only ones that do not normally seem to have problems with the P-0340 &/or P-0344 codes are the original ones that originally came on the original OPDAs.

One of the suspected reasons is the apparent substandard specs of the now available sensors. Another possible (& related to the first) is the significant variation in the air gap (distance) between the sensor face & the tone wheel of the replacement OPDA. Even the best of “hall effect” sensors are very sensitive to the distance from them & the object that trips them.

There was some testing that indicated both the differences in the sensor outputs & the air gap variations of aftermarket OPDAs done by a guy & posted on at least one site.

If you search the P-0344 code on this & other TJ sites you will find a lot of postings, with no real solutions if you no longer have an original sensor.

One possible solution besides trying “new” sensors until you get one that works is to try shimming the sensor to change the gap. That has had some success but not a definitive solution.

Since you went a long time before getting the code you should check the OPDA to see if there is lateral movement in the tone wheel/shaft that may be causing the wheel to be further from the sensor than before or maybe closer or even rubbing on the sensor. If the OPDA bushings are worn that could be the cause.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #3
Since you went a long time before getting the code you should check the OPDA to see if there is lateral movement in the tone wheel/shaft that may be causing the wheel to be further from the sensor than before or maybe closer or even rubbing on the sensor. If the OPDA bushings are worn that could be the cause.

I will check for play. Thanks for the insight. Both original cam sensor and aftermarket sensor are tripping the code, but if the replacement OPDA is toast then it wouldnt matter.
 

·
Registered
Joined
·
3,581 Posts
Of course an original cam sensor can fail but the ones used in the ’05 & ‘06 4.0s seem to rarely fail. Some have been replaced thinking they were bad only to find the problem persisted indicating that was not the problem. If your OEM sensor is, in fact, original that is encouraging & hopefully you find another reason for the P-0344 code. It is also odd to get the exact same code with 2 different sensors & often points to a different source of the problem.

Keep us posted on your findings as this is an ongoing problem & anything that points to a solution is welcome.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #5
Keep us posted on your findings as this is an ongoing problem & anything that points to a solution is welcome.

Turns out im spending next week with the jeep so i will do some more troubleshooting.

I agree that the same code with two different sensors points to another cause. That is why i spent the time chasing for a weird short/open with no luck. I have till friday to brainstorm and ill hit it again over the weekend.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #6
Update:


Got a probe on the signal. There was enough degradation in the square wave to cause the code but not show up in other diagnostics. Crank and Cam Sensor replaced with Standard Ignition parts and so far so good.
 

·
Registered
Joined
·
85 Posts
Update:


Got a probe on the signal. There was enough degradation in the square wave to cause the code but not show up in other diagnostics. Crank and Cam Sensor replaced with Standard Ignition parts and so far so good.

I'm curious to know if you scoped the two new sensors and if so, how did their patterns look?
 

·
Registered
Joined
·
12 Posts
I can not find a shop that can fix my Jeep! We know the cam shaft bearings are shot (removed this ODPA part and looked at the gears). Local shop put in this new ODPA part a year ago, but do not think they looked at cam shaft gears which were probably already wearing from OEM part that is problematic! I do not have the original cam shaft sensor part. Jeep is throwing these codes, sometimes it start and sometimes it does not, they do NOT think it is the PCM, do not see anything wrong with the wiring, I know we MUST do the crank shaft and lifters and timing chain anyway. Local shop even put on a new cam shaft position sensor on my new Crown Automotive ODPA part and that made no difference! I love this Jeep, sooooooo frustrated!
 

·
Registered
Joined
·
12 Posts
Same problem here-can NOT find a solution!

My Jeep has been to 3 shops now including a dealer, none think it is the PCM. Each took out the Crown ODPA Gear that I put in last year and cam shaft gears are worn bad (never new about this OEM problem with this part-too late now). Throwing those same codes, they can not find anything wrong in wiring and voltage anywhere. I have a brand new Crown ODPA with cam shaft position sensor harness on it, should I at least try and throw it in? SOmetimes the Jeep starts, other times not. U can go out to crank it and it turns over but does not want to start, then go out 2 hrs later or so and it cranks up! Then around 45-50mph, starts bucking and sputtering per say!
 

·
Registered
Joined
·
2 Posts
I'm in this same boat with my 2005 TJ @ around 2500rpm it starts bucking in every gear, but if I keep the RPMs down it's fine. I've replaced both the camshaft sensor and crankshaft sensor and spark plugs, oil position switch sensor. Finally decided to take it to a Dealership but they can't seem to answer this. Once my jeep warms up the check engine light goes away and I can go above 2500 RPMs no problems until the next day cold start-up and the whole process starts over. The dealer recommends new crankshaft 15 hours labor the other dealer recommends new block.
 

·
Registered
Joined
·
3,581 Posts
For some reason the cam sensors are sometimes sensitive to temperature. Bad & getting codes when cold then OK after warm up as you are having. One member on a cold morning even removed the sensor, took it in the house, warmed it up, then installed it, started it up & NO CODES! However not real solution, just confirming it is the sensor causing the codes/limp mode.

You are somewhat fortunate. Others get the code/limp mode regardless of temp.

One report is that a Standard Motor Products brand (I think the correct name) sensor worked for him after trying others. Maybe just need to try one after another hopefully can return those that do not work. Not ideal, I know but…
 

·
Registered
Joined
·
2 Posts
Sealership

I think that is my next step because the sensor I purchased was from Oriellys I will try an OEM sensor. The last dealership said they saw scoring on the tone ring for the oil pump/cam gear. Since they see cam wear they advised a new long block. It doesnt makes sense that after driving around and the jeep warms up making sure I change gears under 2500 RPMs the check engine light goes off and the hesitation goes away as well. My issue is Jeep has been around for years I would think the dealership has seen this issue multiple times if not a half a dozen from what I've seen on the forums they should know exactly how to fix this rather then using the shops "8 ball" method.
 
1 - 13 of 13 Posts
Top