How did replacing that stuff work out for you? The temp swings you described don't seem to aweful. Once the grill adds pellets to heat back up, it is always going to overshoot a little, it's just the way it is, you can't control the temp of the flame, only stop feeding pellets, which then it goes into an idle mode, same as smoke, to maintain flame until heat is called for again once the temp drops. Some controllers do a better job at this then others, and traegers seem to be the worst. I have been running a Char Griller 9020 for the past 4 years, and it has always been awesome at only overshooting about 10° or so, and dipping to just 5° below the set temp before recovering unless I open the door. Well, this year I burnt up my first igniter, and it shorted a triac on the board so the new igniter constantly had power and was hot. I ordered a Traeger controller without the P setting, and it was aweful. Smoke setting ran about 225° and I never saw smoke, and 180-225° was always about 260° so the factory idle/smoke setting was way off. Sent that sucker back, order a new triac for my original board, and viola, $5 later and a leason learned I'm back up and working as I feel it should.