continued P0302 error code

1998 ford windstart 3.8L V6.
I have replaced the coil, plugs and wires.

Removed injectors cleaned then and rotated the injectors to different cylinders and still get P0302 misfire of cylinder #2.

When I took the intake off I cleaned the carbon out and clean the ports on the manifold. Which helped the Van run better or the first 75 miles then it started again.

Now it is misfiring any rmp below 2k, and no power to climb hills. No O2 sensor errors.

Could this be a converter backup it to the cylinder (to much back presser) once I cleaned the intake and ports in the manifold I was blowing out a lot of carbon and water.

Could be an electrical connection in the fuel injector circuit is weak. There is power to the injector at all times when the ignition switch is ON.
The PCM provides a ground path to fire the injector.....so there will be a momentary path to ground each time that the injector is to spray a bit of fuel.

You could try swapping the spark plug from cylinder #2 to another cylinder and see if the problem moves with it.

You can also try swapping the spark plug wire for cylinder #2 with another cylinder......swapping them at BOTH the spark plug and the Coil pack.
It is possible to get a new plug or wire that is bad.

Also...make sure that the spark plug wires are fully seated (the metal connector inside the wire boot seated to the metal connector on the plug and coil pack).

New plugs, wires coil still the same error code.

Have you tried swapping the spark cables for #2 cyl and #6 cyl at the ig pack? Does this make the code change?

I would go back to 12Ounce's first point in regards to the signal to the injector. I have seen fuel injector signal testers for under $10. You have ruled out the injectors themselves. Is it possible for the fuel rail to be blocked? I don't know what could block it but........

Is coolant level constant? Oil?

sounds like a headgasket leak OR if it has that goofy plastic intake, ive heard of those leaking too.

it does have the plastic intake, have tested the injector wires, there are all fine. When p0302 starts I get back backfire sounds like thru the intake and not the exhuast also that just started. I have swaped the plugs & wires for testing also. Realy starting to look at the convertor as the problem.

Are you sure you have the spark cables going to the correct plugs?

yes have triple checked them.

While its idling, give the EGR valve a good tap. It may not be seating well and will cause low RPM misfires..

Im currently experiencing the same problems. Could you tell me what u did that ended up fixing it?