3.0 v6 possibly dead cylinder??????

[dirk_dirk]

so i have a 99 ford ranger 3.0v6. running not too rough at idle but enough for me to notice... then when accelerating it runs even rougher and is really doggy... kinda like a diesel with no turbo... no check engine light, and put scanner on it to check for pending codes but none appear... pulled the plugs they all looked brand new(as they should replaced about 6-8months ago) i did a compression check all cylinders where 130psi to 150psi. checked fuel pressure and its at 50psi... according to my manual its in spec(flex fuel motor). no unusual noise from engine... dont see smoke out the tail pipe and coolant and oil look good.... new noise i just heard while tinkering today sounds like metal knocking on metal for about 20-30seconds after engine shut off.... any ideas on what i could be looking at? any other tests i could try?

 

[Stevorocks]

with the engine idling, use a pair of spark plug boot pullers to pull the plug wires one at a time. if the engine runs rougher, the cylinder you unplugged is good. if the engine runs the same, the cylinder is dead. could be a bad ignition wire, injector, or coil pack. be sure to use a boot puller, i would also recommend insulating your arms from the vehicle. when i did this, i used a hose puller, which is not insulated. that didnt feel too good....

i would also double check the plug wires. when i replaced my plugs and wires a month or so ago, i reversed the #1 and #3 wires, resulting in rough idling(i didnt try to drive it, as i knew something wasnt right).