I too have the 2002 van and I've experienced the same issue. I actually posted the problem on this forum back in September of 2005.
It usually happens to me about once, maybe twice a year. The dealer said that our vans fuel pumps go a long time and back in 2005 he didn't think that was the problem but he offered no other solution. (Bring it in, we'll look at it)
I then went to the wiley old veteran at the auto parts store and after I described the problem he went right for a bottle of Lucas Fuel treatment. He said NOT to use anything else. I purchased the small bottle and added to my fuel and soon the sound was gone.
Last summer I think I purchased some bad gasoline since the van was sputtering a bit and I went to another parts store 50 miles away near where I work and wouldn't you know it, he says "use the Lucas, nothing else". So, long story long, use the Lucas!
Olmsted Falls, Ohio
2002 Grand Caravan Sport 3.3L 225,000 miles