Six
A Jeep Wrangler has one spark plug per cylinder.
spark plug loacation on 2006 jeep wrangler sport 4.0 liter engine
A swivel spark plug socket will let you get to #1.
Hopefully this will helphttp://www.4x4xplor.com/sparkplug.html
There is a long black item on the passenger side of the engine. That is the coil. They are under it.
Great link that someone posted on everything you need to know on changing your spark plugs! http://jeep.us41.org/sparkplugs/index.html
Use the same spark plug that came in it, Champion for best results.
.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.
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.
It is moderately easy to change the spark plugs on a Liberty, although it is rather tricky because of the gap between the spark plugs.
The 2005 Jeep Wrangler has 16 valves.
One big one that goes across all 6 spark plugs.