1988 GMC C1500 will not start

The truck has been sitting for three years and I start it anr drive every 2 to 3 months.It finally ran out of gas and I added new fuel to the 30 gallon tank(5gallons). The last time it would not start.I am getting gas past the main filter and I have gotten fuel to the tbi but have not been able to get fuel out of the tbi. It cranks fine, if I pour gas into the tbi whie cranking it will run momemtarily, but still nothing from the tbi.
Got any ideas for me