Check the TPS. There are you tubes that show how but you need decent VOM (volt ohm meter).
If you are near an O'Reilly's rent the fuel pump test kit. It has the fitting for the TBI. Pressure relief is set at 9 psi and it is common problem.
Sounds like just dirty injectors, all thing else being equal. Other possibility is vacuum leak some where.
As suggested go around engine with propane gas from torch, or spray of starting fluid, even WD40 is combustible.
If you shoot near where a leak is, RPM will flare and then drop back down.