Charcoal temperature won't regulate
You can regulate the temperature by adjusting the grill dampers. If you’re not able to achieve the temperature you need, check for any gaps in the damper. If the damper is bent or warped, it will not create an efficient seal, and you’ll need to buy a new grill damper. Each charcoal grill has a unique configuration, so make sure to check your manual.
The intake damper is the main temperature control in the grill and brings oxygen to the fire. The intake damper will be on the grill firebox or the offset smoker fire box. When starting up the grill, leave the damper open so oxygen can get to the flame and feed the fire--if you close the damper, oxygen can’t get to the fire and it’ll die off. For hotter temperatures, keep the damper open. Partially close the damper to starve the fire of oxygen and cool off the grill--open the vent back if you notice the temperature drops too low.
The exhaust damper will be on the smokestack of barrel-style charcoal grills or on the lid of non-barrel charcoal grills. The exhaust grill damper allows heat and smoke to escape the firebox. By opening the vent, you release the excess smoke and create low pressure inside the grill. The low pressure pulls oxygen into the intake vent on the side of the firebox.