Here's my experience with the P0340 code, I apologize if the post is long, but I hope it'll help anyone having the issue.
First I replaced my OEM Wonky PCM with a Wranglerfix unit, it restored communication with my code scanner and eliminated all the false O2 sensor, and coolant temp codes that were present, but I still had the P0340 code and hard starting. So I consulted the FSM and started running down the trouble tree.
After several checks with a DVOM ended up with finding a short in the Cam Sensor Signal wire.
Did some investigating on the harness and found some bare wires on the harness to the CMP sensor and Alternator (Harness runs along the engine )
I repaired the wires, cleared the codes, but the P0340 came up again. Sarted down the FSM diagnostics again, found the same issue. Short to ground in the sensor signal wire. My luck two shorts in the the same wire!!! Instead of chasing wires on the harness, I just decided to run a new bypass wire from the firewall to the sensor harness. Did the checks again and no more short to ground. I cleared the codes and Vroom! my TJ fired right up. and first time in many years the check engine light is off!!!
Hunting for the camshaft Position Sensor wire for a good bypass point
New bypass Camshaft position sensor signal wire
All good! (for now LOL!)
First I replaced my OEM Wonky PCM with a Wranglerfix unit, it restored communication with my code scanner and eliminated all the false O2 sensor, and coolant temp codes that were present, but I still had the P0340 code and hard starting. So I consulted the FSM and started running down the trouble tree.
After several checks with a DVOM ended up with finding a short in the Cam Sensor Signal wire.
Did some investigating on the harness and found some bare wires on the harness to the CMP sensor and Alternator (Harness runs along the engine )
I repaired the wires, cleared the codes, but the P0340 came up again. Sarted down the FSM diagnostics again, found the same issue. Short to ground in the sensor signal wire. My luck two shorts in the the same wire!!! Instead of chasing wires on the harness, I just decided to run a new bypass wire from the firewall to the sensor harness. Did the checks again and no more short to ground. I cleared the codes and Vroom! my TJ fired right up. and first time in many years the check engine light is off!!!
Hunting for the camshaft Position Sensor wire for a good bypass point
New bypass Camshaft position sensor signal wire
All good! (for now LOL!)
