I have a 2002 disco with 100k started running rough about a week ago codes for miss firing on cylinders 5 and 6 installed new plugs and wires same issue installed new coil packs came out of it reset check engine light drove it 20 miles check engine flashing and codes for miss firing 0n 5 and 6 again. what should be my next place to look?

 

Well for starters, stop driving the truck. The missfires will damage the catalytic converters. Unfortunately, that's all I've got for you. I'm sure someone here can help you investigate further.

 

there are a half dozen threads going on misfires just this week. Read all of those. Then do a search. Any responses that you get will be a redundancy. Very significant number of variables. If you are feeling froggy you can do a google search too. Unfortunately there is nothing outstanding of the 2004 Disco as your misfire issue is comparable to that of any other make and model vehicle. You could try this.
http://www.myautorepairadvice.com/p0300.html

The source of your misfire could be anything from a vacuum leak to a cracked engine block