TPI blows it does not flow enough air in stock form and the aftermarket solutions are very costly once you get everything purchased and installed. USally wiring harness, upper lower and throttle body need to be replaced along with injectors and computer just to hit 300 hp. then the troubles really start costing money.
Junk the TPI install carb and intake drive car for next 20 years without problems.
Some gotchas for tpi.
Wiring gets old and brittle and cant be repaired easily. corrosoin will finally end the wiring problems with a full on replacement that is not as easy as one might think.
For your current problem check all the grounds and make sure they are clean and brite if you have never done it before its a good project for the next time you see the car. At least you will have a direction that is not wrong even if it is not a solution.