2015 JK Wrangler P0456 Code, Gascap, EVAP system smoked no leaks

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appst8design

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2015 JK Wrangler 3.6L with P0456 small EVAP leak. Started out with just the P0456 code but now has gas cap warning as well.
-Tried erasing code with OBD scanner (CEL came back on)
-Replaced gas cap, cleared CEL, CEL came back on.
-Replaced Vapor Purge Valve, cleared CEL, CEL came back on.
-Took to mechanic to have EVAP system smoked (didn't have any leaks) and replaced Evaporator System Integrity Module Detector, cleared CEL, CEL came back on.
-Mechanic suggested there was a TSB for this exact problem (I can't find it) but it required reflashing PCM by dealership. Dealership says they don't reflash used PCM's.

Would just resetting the PCM clear the permanent gas cap and CEL code that I just can't seem to get rid of? Any other suggestions on how to fix?

Appreciate any help on this issue.
 
Emissions related codes usually need an explicit number of clean starts and/or a certain accrued mileage before they will stop generating the code. Have you driven the vehicle much since replacing the parts??
 
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tJKrider said:
Emissions related codes usually need an explicit number of clean starts and/or a certain accrued mileage before they will stop generating the code. Have you driven the vehicle much since replacing the parts??
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Each time I've drove it until it came back on. I reset the PCM this evening and both went away (before I could only get CEL to shut off). I'll repost if it stays off.
 
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Did u research and make sure that the exact model mopar fuel cap was installed? It definitely makes a difference. The ESIM module that was installed must have the green o-ring not the black one. Trust me when I say these are essential to the system sealing up. 🍺🍺
 
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BigAL07 said:
Did u research and make sure that the exact model mopar fuel cap was installed? It definitely makes a difference. The ESIM module that was installed must have the green o-ring not the black one. Trust me when I say these are essential to the system sealing up. 🍺🍺
Click to expand...
Cap was OEM from MOPAR so I'm sure its the right one.
 
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