In the engine.
Six
All spark plug gaps are adjustable.
spark plug loacation on 2006 jeep wrangler sport 4.0 liter engine
A swivel spark plug socket will let you get to #1.
A Jeep Wrangler has one spark plug per cylinder.
Great link that someone posted on everything you need to know on changing your spark plugs! http://jeep.us41.org/sparkplugs/index.html
.035 is the correct gap for your Wrangler's spark plugs. That gap is correct for at least up to 2006 and likely for 2007-2009 as well.
Hopefully this will helphttp://www.4x4xplor.com/sparkplug.html
Use the same spark plug that came in it, Champion for best results.
There is a long black item on the passenger side of the engine. That is the coil. They are under it.
For both 4 & 6 cylinders, they are on the passenger side of the motor. Follow the plug wires to the plugs in the side of the engine.
eHow Auto Center - 2012 Changing Spark Plugs 1-2 was released on: USA: 1 October 2012