Many/most Traeger owners find that the controller set point and the actual measure temperature differ, sometimes by as much as 50 F. When preheating, it is common for the temperature to overshoot the target, then it should settle down. The controller does not try to maintain a tight temperature variation as they are tying to simulate the burn of an offset smoker. If you were feeding manually, you could not maintain a tight variation. If you are trying to operate below 200F, the controller will have a more difficult time holding the setpoint. On my Ironwood, I normally operate at 225F cook temperature, which requires me to set the controller to 230F. The temperature will vary about +/- 5 degrees from target. If I want to cook at higher temperatures, such as roasting vegetables at 400F, I increase the temperature setpoint 50F at at time to prevent overshooting. I have to set my controller to 450F to achieve a cook temperature of 400F, but every grill will be different. Nearly everyone on the forum will caution you not to trust the temperature probes provided by Traeger. Always purchase 3rd party temperature probes and check them for accuracy. Many people like using probes like Fireboard or Meater, but they are expensive and you can find less expensive probes that will work as well. The latest Timberline XL grills come with Meater probes. Traeger recently purchased the company. It is unlikely that the Meater probes will be used on any but the top of the line grill models.
After almost 20 years I have given up. My first Traeger lasted me 15 years and was a wonderful smoker. In 2018 I looked forward to using my brand new Pro 34. The first year I got about 5 cooks before it quit working. Traeger to their credit replaced every part on the smoker. Last season it would only get 135 degrees. I pulled the auger and it wasn't packed with pellets. I gave up this winter and bought a Camp Chef which so far is working as expected.
