i have a 1997 f150 with the 4.2 6 cyl and it runs poorly.the cats start glowing and the plugs looked like they were soaked with gas.compression great in all six cylinders,all six coil towers are firing.pulled cats off to see if they were plugged up but it did not make a difference in the way it runs and it almost looked as if unburnt fuel was coming through exhaust.some one please help me out here.thank you in advance.

 

I would start with pulling the vacuum line off of the fuel pressure regulator and see if there is any fuel in the vacuum line. If there is, then the regulator's diaphram is breached and the regulator needs replaced. If the fuel pressure regulator is OK, then I would check the O2's. They can be sending a false "LEAN" reading to the CPU that causes the injectors to increase their pulse width thus injecting excess fuel. O2's can appear OK to the CPU, but are actually bad. Were all 6 spark plugs soaked with fuel? If only one bank, then I would go for the upper O2 on that side.

This should get you started. Let us know.