Now that I finally have my engine running properly and not throwing any check engine lights, this issue has become more obvious to me. When the engine is idling, especially after a cold start, when I hit the throttle it will dive down in revs before rebounding and revving up like it should. It is never enough to stall, but it makes it difficult to start in first gear, especially with someone who isn't amazing driving stick (yet). I am thinking maybe the TPS? My MAF is brand new so I do not think it is that, and the wires on the TPS are switched like they are supposed to be. I do have a leak in my exhaust I am attempting to figure out and fix, so maybe that is part of the problem as well? Any advice or troubleshooting welcome.