Hi, first of all, everyone here are super clever when it comes to diagnosing problems, you've all saved me so much time and effort when it comes to little things, its much appreciated!

I have an 05 F150 Crew with 5.4. after the latest deep freeze (i'm in Alberta) the truck started to idle very rough, I changed the fuel filter and that seemed to help the idle but now when cold, it is nearly undriveable, all it does is backfire and nearly stall out with massive amounts of exhaust. once running for a about 10 minutes, the backfires stop and it is drivable up to around 80km/hr, then it is very shaky and rough.. any suggestions

Please note that I recently had injectors and plugs done

thanks, any suggestions would be appreciated