Do a good underwood inspection. Check all hoses to make sure there are none cracked, disconnected, etc. Check all electrical connections to ensure all are seated and wiring is good. O2 wiring may be a bit hard to see all of, but ensure what you can see is in good shape. Definitely inspect the throttle body and spray pattern as recommended. Change plug wires if they arent newish and in good shape. Make sure you are running the correct plugs (no fancy wannabe plugs). Engine gets up to proper temperature ok, check engine light works as it should and no codes?