Itzdwoodduhh

Soo this has been troubling me, my 92 lumina idles fine in park and neutral. When u put a load on it (in gear) after it warms up it will stall out going down the road when u hit the brake u can put it in neutral crank it right back up throw it n drive n continue that process. Also while riding down the road it will knock and act like it won't take any fuel sometime. Things I've already replaced.
Fuel filter and fuel pump.
Engine coolant temp sensor
Alll spark plugs and cables
O2 sensor.
Any ideas. This has me completely stumped