I just bought a 2014 it has the harness tab just done and it was reflashed at the dealer before I bought it. I bought it in September it was fine really untill it got cold put. Now upon start up it sputters and under light load is stumbles anything around 2000 rpm. I've never beaten or launched it haven't even seen full boost. I did do the muffler resonator delete. I searched on Google and found many similar post but none seem to have found a fix or a solution to this problem. My commute to work is short and I've never had the oil temp in the middle highest it's ever gone is a quarter sorry forgot the actual temp it says there. Is my car not at optimal operating temp and this is why? I run only 93 which is hard to find where I live. This can't be how the car runs I haven't pulled plugs yet but I can't believe under that light of a load it would be an issue maybe at wot but I'm not a mechanic. I want to mod the car intercooler, downpipe, tune and advebtually go big turbo someday but this kinda worries me. Any help is greatly appreciated as I said I Know this has been covered but seems like no answers. Could Ford have done the table wrong? Also brought it to the dealer and under the drivetrain warranty they wouldn't cover it unless I paid 140 for diagnostics does this make sense? I just gave them 17,000+ dollars and have only 2000 miles on the car dosent sound right to me the dealer sucks wish I knew that before I've never had problems with warranty even with my other big turbo cars in the past. Maybe I had a dealer who didn't care.