Idling issues and engine shutting off

So my car listed above is the j20 model has been having idling and shutting down issues a while now. I have tried changing cam and crank sensors, servicing fuel injection system, changing plugs, regular air filter change, servicing throttle body, trying known working coil packs and using regular fuel treatments. While it has improved from shutting off constantly once at idle to shutting down only when under higher load such as on inclines or reversing, the problem is still there and the vehicle idles erratically sometimes.
Vehicle performance is high and responsive on some days while not on most days. Any suggestions?