OK, so back febuary my truck developed a weird issue. The truck would start fine and so I would back out of my driveway and about 10 seconds down the road it will miss very bad and have almost no power for about 20 seconds BUT if I went WOT it would clear up in about 1 second and be fine for the rest of my drive. It would do it every single time I started the truck whether it was hot or cold. I just finished swapping in a newer motor(not for that reason) and the problem went away. . . . . for about a week then came back. I removed the throttle body spacer and no change. I had a whole other throttle body setup from the other motor so I swapped it and no difference and it almost seemed worse but I cant be certain. All plugs are brand new, wires are under a year old, and I am running a superchips programmer. It kind of seems like the comp has to re-learn every single time I turn the truck on. Yes I do have 2 codes. One is bank 1 lean and lack of 02 switch but I have always had these codes even when it ran good. I really have no idea anymore. I ran the scanner while running my truck but I couldnt decipher anything from it. Coil breaking down maybe? Its just really wierd that it did it before the swap then it stopped when I put the new motor in then started again a week later. I literally get about 20 seconds of the truck running like complete crap then it smoothes out and runs like a top.

 

You need to find and fix those issues before you can even address driveability issues. You have something wrong that needs to be fixed.

You should also return the tune to stock till you get this figured out.

If you are running a K&N, when was the last time you cleaned the MAF?

 

Starting to hate this truck. I have been having to fix or replace parts every single week. K&N yes and when I swapped the motor I cleaned the maf and throttle body. I actually just put a new o2 on the drivers side upstream and the missing went away but now I have bank 1 lean and bank 2 lean codes :s. Im going to go over all my vacuum lines first.