Do a gas check—it's essential for safe, efficient cooking, especially if a grill's been idle.
Inspect the tank. Run a leak test. Coat the regulator, valves, and hoses with soapy water, then turn on the tank to pressurize the system. Look for bubbles, which indicate escaping gas. Tighten connections and try again; if there's still a leak, replace the hoses or the tank, if need be. Next, if your grill lacks spider guards, use a bottle brush to clear out debris or insect nests from the venturi tubes, which connect gas to burners. Finally, fire up the burners without the grates in place and look for spots that aren't flaming evenly. Once cool, clear any blockages in the burners with a paper clip.