Have a 96 2.2 accord runs fine for 5 mins then starts missing badly .code.PO303

P0303 indicates a misfire at cylinder 3. You have verified all plugs, wires, etc are routed correctly, are of good quality? Did you check base engine compression to see if cylinder 3 is low in compression compared to the other cylinders? You could also have a fuel injection issue.

Inspect and clean/tighten all engine grounds. ESPECIALLY the cluster on the intake (back of engine towards firewall, under throttle body). I have seen many cases of poor driveability caused by ground issues.