Hello and welcome to JustAnswer.My name isXXXXX have checked diesel powertrain manual and haven't found P0069 trouble code. Can you recheck and give me a correct DTC number?
p0069 is an OBD2 code for Barometric Pressure Correlation. mopar says the jeep is obd2 certified. im a gasoline mechanic and am completely lost on this 2.8L vm motori common rail turbodiesel motor (other than giving it an oil change. any other system on this car i can rebuild blindfolded). I doubled checked and the car does have and OBD2 emittions module. I deleted the p0069 in an effort to confirm it will pop back up and still have yellow emissions light, and the emissions module light on my scanner is flashing. local dealership doesn't employ a diesel mechanic (small town and we dont have a lot of farm land). Things I've done: Removed EGR valve & cleaned (reinstalled), removed and cleaned MAP sensor (reinstalled), Removed & cleaned air pressure sensor (reinstalled), open gas cap to equalize pressure, retraced & tested all wire back to ecm (all wires good. all voltages to and from sensors good). I'm starting to think because the engine is doing this intermittently that its just vapor lock in a dirty engine.
Well, I checked genuine Chrysler Diesel Powertrain diagnostics and can assure you there is not P0069 trouble code for those 2.8L VM Motori engines. It sounds that you scanner shows wrong number. You should use a DRB III scan tool in order to properly diagnose the car. There are two problems I have seen on those engines:
1) Turbo air charge hose splitting
2) A glow plug failure.
Even you local dealer does not employ a diesel experienced technician, they do have a DRBIII scanner so ask them to scan this Liberty and let me know the correct trouble code number and will try to give you correct directions.