I have a Char-Broil stainless gas grill that is about 2 years old. I have 2 20lb propane tanks for it that I switch out. When one of the tanks got low, I hooked up the second one and I wasn't getting any gas. The 1st tank still worked OK, so I re-filled it. I haven't taken the 2nd tank back to exchange it, yet. We've been using the 1st tank now for a couple of months and the other day noticed the flame had gone really low. I checked the tank and it was at least still half full... Before I spend a bunch of money exchanging tanks that don't need exchanging, is there anything else I should check? What could cause a lack of pressure? Duh, I just thought that it sounds like a regulator vent plugged or a bad regulator. I'll check that tonight after work. Any other ideas?