My weber gas grill won't light. About a month ago, I had a BBQ and was unable to start the grill. I went to a home depot and traded in my existing propane tanks for new ones. This appeared to fix the problem as it lighted right up. Last weekend, I tried again to grill and ran into the same problem. Knowing that I had 2 relatively new propane tanks, I didn't think it was either. I attached and reattached each a couple of times to no avail. Thinking it could be the trigger, I used a lighter - to no avail. I do smell propane but perhaps not to the same extent as before.