Honestly, we have to see the tune that's on the car and what the DTC is to pass judgement. If the car is in otherwise good working order... i.e. headers don't leak, no vacuum leaks, then I would cover maintenance basics. If the plugs and wires are original then get some new delco wires and Autolite 104's and set the gap to .055. If the tune is anything like ZZP's, the power enrich TPS enable could be set really low like 30% across the board. I raised my PE TPS enable back up to stock because it was going in to PE way too often when it was unnecessary.