I had fuel flow issues before and I thought it was the regulator, but sometimes I had a nice flame and others it wimped out. What became more consistent was opening the valve on the tank and purging a few blasts. You can tell a difference from good flow or a cocked seat. Leave the tank valve open and hook up the BBQ. See if that helps.
Seems the new ones go down to "low flow" every once in a while. Turn off gas and disconnect BBQ and hook back up, thats worked for me....best solution I found is to switch to gas and don't worry about it any more