Multiple CELs when cold?

[Tom Andersen]

I have a 2006 LJ, 4.0, auto trans, bought in May of this year. When temperatures drop to around 30 degrees or less I start getting cel's. They seldom repeat, are unrelated, and there are no symptoms associated with them. I am wondering if the problem might be with the pcm? The place I bought it from sprayed the whole vehicle with some kind armorall or something. They saturated the car from top to bottom, under the hood, inside the passenger compartment, everywhere. Is it likely it got into the pcm? I was going to pull the plugs out and clean them with electronic contact cleaner but don't know if that would be an acceptable fix?

Or might I be having another issue?

 

[Chris]

What are the check engine codes you're getting? That will be a tremendous help in diagnosing this issue.

 

[Tom Andersen]

What are the check engine codes you're getting? That will be a tremendous help in diagnosing this issue.

Chris the codes are

p1684 - battery power to module disconnected
p0344 - camshaft position sensor
p2096 - post cat fuel trim system too lean bank 1
high fluid temperature in transmission(I didn't get the code #)

no symptoms until yesterday, engine cut out when under load and engine died when backing up but restarted easily. As soon as the engine got warm the cutting out stopped. One time the p0344 code cleared itself.

 

[Chris]

P1684 is likely one of the following issues:

• Battery was recently disconnected
• Transmission Control Module (TCM) was replaced or disconnected
• Faulty Transmission Control Module (TCM)
• Transmission Control Module (TCM) harness is open or shorted
• Transmission Control Module (TCM) circuit poor electrical connection

As far as where to start, either one of two things is going on... You recently disconnected the battery and caused this error, or you have a TCM module that is going bad or has a short (it's probably the former, as it's not unheard of). Disconnect your battery and let the vehicle sit unplugged for 10 minutes or so, plug it back in and see if the error code is still there.


P0344 is likely one of the following:

• Faulty Camshaft Position Sensor
• Camshaft Position Sensor harness is open or shorted
• Camshaft Position Sensor circuit poor electrical connection
• Faulty starter motor
• Starting system circuit
• Dead (Weak) battery

This is a good time to test your battery and make sure it's actually still good (it can still be weak even if it starts). If it's good, it sounds like it's likely your Camshaft Positions Sensor which is a common thing to go wrong. Replace it with an OE Mopar sensor, any other brand of sensor will not work (trust me, the aftermarket brand sensors all the auto part stores sell have nothing but issues with our TJs electrical systems).


P2096 is likely one of the following:

• Faulty oxygen sensor
• Oxygen sensor harness is open or shorted
  
• Oxygen Sensor circuit poor electrical connection
• Exhaust leaks
• Contaminated oxygen sensor

It's possible that your O2 sensor in bank 1, sensor 2 is bad. Go pick up an NTK (made by NGK) sensor and replace the one that's in there. For more info on which oxygen sensor it is, see this thread: The Official Jeep Wrangler TJ Oxygen (O2) Sensor Thread

There's also a thread here where someone else was having the same issue with error code P2096. It's worth checking out: P2096 error code

 

[Tom Andersen]

P1684 is likely one of the following issues:

• Battery was recently disconnected
• Transmission Control Module (TCM) was replaced or disconnected
• Faulty Transmission Control Module (TCM)
• Transmission Control Module (TCM) harness is open or shorted
• Transmission Control Module (TCM) circuit poor electrical connection

As far as where to start, either one of two things is going on... You recently disconnected the battery and caused this error, or you have a TCM module that is going bad or has a short (it's probably the former, as it's not unheard of). Disconnect your battery and let the vehicle sit unplugged for 10 minutes or so, plug it back in and see if the error code is still there.


P0344 is likely one of the following:

• Faulty Camshaft Position Sensor
• Camshaft Position Sensor harness is open or shorted
• Camshaft Position Sensor circuit poor electrical connection
• Faulty starter motor
• Starting system circuit
• Dead (Weak) battery

This is a good time to test your battery and make sure it's actually still good (it can still be weak even if it starts). If it's good, it sounds like it's likely your Camshaft Positions Sensor which is a common thing to go wrong. Replace it with an OE Mopar sensor, any other brand of sensor will not work (trust me, the aftermarket brand sensors all the auto part stores sell have nothing but issues with our TJs electrical systems).


P2096 is likely one of the following:

• Faulty oxygen sensor
• Oxygen sensor harness is open or shorted
  
• Oxygen Sensor circuit poor electrical connection
• Exhaust leaks
• Contaminated oxygen sensor

It's possible that your O2 sensor in bank 1, sensor 2 is bad. Go pick up an NTK (made by NGK) sensor and replace the one that's in there. For more info on which oxygen sensor it is, see this thread: The Official Jeep Wrangler TJ Oxygen (O2) Sensor Thread

There's also a thread here where someone else was having the same issue with error code P2096. It's worth checking out: P2096 error code

Chris thanks for your help, I have some direction to try.

Tom

 

[Chris]

Let us know what you find!

 

[Tom Andersen]

Let us know what you find!

Will do. I just returned home from buying a new agm battery.

 

[Tom Andersen]

Soon after replacing the battery I got the code 0344 again. I replaced the camshaft position sensor and have been waiting for some cold days which finally happened. So far I am not getting anymore cel's.

 

[Tom Andersen]

Well it was cold this morning and the code 0344 came back but cleared itself after 4 starts. Also code 0456 (slow leak in evap system) has been back after I thought I found that issue.

 

[Jerry Bransford]

Is your engine warming up properly and within a reasonable amount of time? Do you have the correct 195 degree engine thermostat installed? Could someone have installed a "fail safe" thermostat that has failed in the open position preventing the engine from warming up properly?

 

[xackley]

I would inspect and use de-oxit on the connections to the pcm.

 

[Tom Andersen]

Is your engine warming up properly and within a reasonable amount of time? Do you have the correct 195 degree engine thermostat installed? Could someone have installed a "fail safe" thermostat that has failed in the open position preventing the engine from warming up properly?

Jerry, yes the engine warms up properly, it has the correct 195 degree thermostat installed June of this year. This happens when the outside air temperature is cold. The cel pops up instantly when first starting. The engine cuts out bad if given any throttle barely above ldle. If I drive the car until it reaches operating temperature, shut it off for 5 to 10 minutes and then restart, the bad cutting out is gone. Today and another time after the same scenario and 4 or 5 restarts the cel is gone until the next cold spell. The engine warms up quickly and the temp gauge needle stays just below 210 degrees. The heater is plenty warm also.

 

[Tom Andersen]

I would inspect and use de-oxit on the connections to the pcm.

I bought a large can of deoxit just for that purpose but didn't know if that would be an acceptable fix. What about using the contact protector that goes with it?