[Kengine]

I have a 2006 Elise I've been having difficulty tracking down a P0171 with the past few months. I've tried multiple things to repair it, and it just keeps returning. The car has been smoke tested for vacuum leaks, the PCV valve, coils, spark plugs, and the MAF have both been replaced. It was also inspected for any exhaust leaks by the dealer. The dipstick tube was checked as well. Here is monitoring via DashCommand I performed while the car was idling, and with a few revs. I'm looking for anyone who understands this stuff to give me some insight on what they might see in the diagnosis. Any help would be greatly appreciated.

IMG_1911_zps2dc2cae4.mp4 Video by Razorub | Photobucket

 

[Kengine]

A video of me cruising around at 2500 rpm and monitoring:
IMG_1914_zps13df63d0.mp4 Video by Razorub | Photobucket


Sitting and holding it at ~2000rpm:
IMG_1916_zpscaca6414.mp4 Video by Razorub | Photobucket

 

[Spumoni1984]

Just pm'd you...have you tried going back to stock cat?