Question

car ran perfect then all of a sudden started stalling and running really rough. Was unable to keep it running unless I floored the gas pedal. Hesitation from engine.replaced starter plugs and wires and car ran great again for about 5 minutes (idling) drove it to driveway from garage, next morning it stalled out again.replaced the fuel pump and fuel filter and car ran perfect again for about 30 mins, then started running really rough.It fires up again but runs really rough, after a few start ups it gave a code of p0300 random cylinder misfire.Putting back old spark plugs as recommended to troubleshoot if new ones are faulty.

Answer 1

​  Check the fuel pressure regulator with the engine running disconnect the the vacuum connection if there is fuel coming out replace the fuel pressure regulator