97 Toyota 4Runner 4WD 3.4L Engine Light On with Persistent P0301 Code

The engine warning light came on in my 1997 Toyota 4Runner 4WD with a 3.4L V6 engine. After scanning, the vehicle displays error code P0301 (Cylinder 1 Misfire). I have already replaced all spark plugs and ignition cables, had fuel injectors professionally cleaned at a Toyota dealership, checked compression which reads between 178 to 180 psi, cleaned all electrical connectors, replaced coil pack #1, installed a new air filter and fuel filter. I never use regular gasoline. After clearing the code, it reappears consistently. Despite spending over $500 on repairs, the issue persists. I'm at a loss as to what the root cause might be. Any insights or troubleshooting steps for this persistent P0301 in a 1997 Toyota 4Runner 4WD would be greatly appreciated.