My 2012 LR4 has the gas cap warning light coming on intermittently along with the check engine light (constantly on) for the past 4 weeks. I had the DTML valve, charcoal canister and new OEM gas cap installed, cleared the codes but the lights remain on. Also experiencing rough start after filling the tank and have to hit the accelerator to keep the engine running, drop it in drive and vehicle drives fine and starts up with no issue until the next fuel up. Anyone have thoughts on what it could be? Thanks

 

Purge valve is stuck open. This system pressurizes the fuel tank and lines to check for leaks, when the car is off. It attempts to "seal" the system by closing all the valves and with the purge valve sticking open, that is the leak source.
Also, since the valve hangs open, vapors from the tank during refueling are pushed into the intake manifold and flood the engine, causing the hard/rough start.

 

Correct, I had my independent LR mechanic replace the purge valve assembly, issue has finally been resolved. Thanks for the feedback !