Hey, my 2005 ford ranger 3.0, it runs really rough in park at 3000rpm, I changed the plugs and wires and also changed the coil pact, any help will be appreciated.

 

Welcome to the forum

Rangers all have REV limiters that prevent RPMs higher than 3,000 when in Park or Neutral OR.........if speedometer shows under 5MPH, except in 4Low on a 4WD
So you shouldn't be able to REV engine over 3,000 when stopped, computer limits spark and fuel

 

^^^ X2. As Ron posted there is a rev limiter in park / neutral. When it hits around 3000 rpm, engine will stumble and miss like it's going to quit. Acts like the coil pack is shot or plug wire / spark plug is bad. Take it out for a spin and rev it up through the gears...no more problem.