The first thing I would do is a compression test on #6 and if over 125 PSI you are okay, next look at the spark plug to see if it is black with soot, if so, the fuel injector is not spraying correctly, and the spider injector will need to be replaced.
This could help as well:
CAUTION: Use care in removing the fuel injectors to prevent damage to the electrical connector terminals, the injector filter, and the fuel nozzle.
NOTE: The fuel injector is serviced as a complete assembly only.
CAUTION: Also since the injectors are electrical components, these injectors should not be immersed in any type of liquid solvent or cleaner as damage may occur.
1. Disconnect the negative battery cable.
2. Relieve the fuel system pressure. Refer to Fuel Pressure Release Procedure.
3. Remove the Upper Manifold Assembly. Refer to Engine Mechanical.
4. Remove the Fuel Meter Body Assembly. Refer to Fuel Meter Body Assembly.
1. Install the fuel meter body assembly. Refer to Fuel Meter Body Assembly.
2. Install the upper manifold assembly. Refer to Engine Mechanical.
3. Connect the negative battery cable.
I have also seen the EGR valve not close all the way which can affect the cylinder misfire as well so remove it to see if it needs to be cleaned.
Check out the images (below). Please let us know what happens.
Images (Click to enlarge)
Thursday, January 12th, 2023 AT 5:05 PM