Need help with a 2009 f150 4.6 vin w.It has a multiable miss fire on cylinders 34568 put new plugs and coils in it.Still runs the same did find some coolant by thermostat and some coil boots where wet but pressurized system couldn't find and leaks and it held pressure it seems to run fine if you bring rpms up to about 2 grand anyone have any ideas what to do thanks