Just bought 97 4x4 4.3L . No problems except it hesitates when any load is on it. Got a free diag. said it was high/low/ fuel pressure. Changed filter, and nothing. Diag also said it was a misfire in cylinder one. New plug and wire in 1, still hesitates. Could it be a bad point in the cap? running out of ideas

 

When was the last time a full tune up consisting of plugs, wires, cap, & rotor was performed?

What was the specific OBD2 trouble code (Pxxxx) that was reported when the PCM was scanned?