96 caravan, won't start

I have a 96 Caravan, 3.3 eng, it has been sitting for 2 years, I would start it every 2 months or so, last time I tried it would not turn over and when I made sure it had a full charge and good conection on the battery, it turned over slowler and would not start, it gets spark, I tried to spray starting fluid into the intake and it still will not start, any clues, Please help

-- Message posted using