Truck spits and sputters

I highly suspect that you have raw fuel in your evap canister and the possibly the purge valve is sticking. What happens is when you get fuel in the canister rather then just vapor, it breaks down the charcoal and it gets into the purge and causes it to stick.

Once this happens the engine actually runs too rich and starts to sputter.

I would go ahead and replace both these components and retest the vehicle.

Let me know if you have questions about this and we can go from there. Thanks