rubyred5.0

Alright so please anyone who can solve this or help me. So I bought and installed the C&L Racer Intake for my 2015 5.0. Installed it and the Lund Tune they provided and it worked well, so the next day I got the headers installed and the Tune was made for the headers already and I’ve been tripping the P0135 code all the times, always Heater Circuit. Then whenever I give it throttle it shows the P0300 for Multiple Cylinder Misfire and P2004 and P2011 for Intake Manifold Runner Control Stuck Open. I initially thought it was just the extensions and it turns out they had only installed it on my driver side because the passenger side was long enough to reach, so I bought new extensions from BBK and still no success. Be mindful the other codes only show up whenever I give it slight to hard throttle. If not it’s only P0135 that shows up, please any help is very much needed right now.