the cylinder numbers (front-to-rear) ................. 1-2-3-4-5-6 the firing order is ............................................... 1-5-3-6-2-4 a diagram of such can be found in the hanyes repair manual check your local autoparts store for it.
A Jeep Wrangler has one spark plug per cylinder.
The diagram.
.035 inch
Count the number of spark plugs, 4=4 cylinder, 6=6 cylinder.
I think it's .035
.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.
.35 inches .89mm
this is the proper
4 cylinder has only 4 spark plugs and is shorter than the 6.
Its prob the same as the 2.8 diagram on this link: http://media.photobucket.com/image/spark%20plug%20diagram%20chevy%203.0/roundcarly/chevy_firing_orders.jpg
removed plug wire, remove spark plug, gap new plug to spec. and reinstall. Repeat for every other cylinder. Would recommend replacing plug wires, cap and rotor when replacing spark plugs.
Try replacing the plugs and wires