Q: Multiple cylinder misfire detected. Changed the distributor, fuel pressure regulator, injectors and the coil.

Hi there. Check the spark plugs in the engine and see if they have a bold spark. If the spark plugs and wires are old, they can cause the electrical current to flow slower than normal to the cylinder causing the engine to have misfires. If you have replaced the spark plugs and wires, then check the camshaft position sensor out and see if the sensor is working. If the sensor is not working, then the computer is relying on the crankshaft sensor to run the engine, but with the camshaft sensor not working will cause the engine to also have multiple misfires. If you need further assistance with your engine misfiring, then seek out a professional, such as one from Your Mechanic, to help you.