Runaway UDS

I recently built a UDS and today I am doing my third cook. My cooking temp ran away from me, but I finally have it steady at 350. This is higher than I wanted, but after reading many posts I think my butt and ribs will be ok, just hopefully not dry.

Any ideas on what could have caused this? I think it may be partially because I got distracted and the temp got higher than planned before I started shutting down valves.

I also am using a different lid this cook. I previously used the lid from my Weber, but recently found a no name kettle in the trash with a hinge. I mounted the lid, but it was a little small and I bent out the rim and it leaks a little.

Would the leaking lid be the cause of the higher temp or maybe a leak elsewhere in the UDS?

Thanks for all the help, this site is awesome!

After doing a little poking around the site I am thinking that maybe I should try a BGE replacement gasket to see if that helps the lid leak.

My first thought was that it wasn't the lid, because I too thought it would just be like additional exhaust, but it was the only thing I changed from the first 2 cooks.

I think Bludawg is right, starting to think it may just have been my own fault by letting it get to hot before slowing down.