Shortly after I applied the sauce for the final step while doing 3-1-1 ribs, I noticed dark bad smelling smoke started rising from the DFMT. I raised the lid and saw there was a fire in the pit. My guess is some drippings had fallen by the PS into the coals and ignited.
I didn't want to sauce to absorb this dark smoke so I pulled the ribs off a bit early. The ribs were excellent but if left me wondering how you would extinguish a grease fire in the pit if you are still in the middle of your cook?