2 weeks ago I was 50 miles from home and I stopped for fuel. I needed 10 gallons of fuel. Going 30 miles after I added fuel, the van began to buck or back fired lighty when I applied the accelerator. When I fill the tank up the van runs perfect, when I get near 1/2 tank the bucking and back firing return. I added a can of Coastal Foam gas treament 2 days after this started. What are my options?
I would consider the possibility of a weak fuel pump or a clogged fuel strainer (filter)
Drop the tank and inspect the contents.