There is a $2.00 air filter on the bottom of the gas tank vent (charcoal canister) that can cause those symptoms when dirty. You got it muddy from the sounds of things. Quick test is to crack open the gas cap and drive it that way for a bit.
A blocked air filter can also cause those symptoms.
86/00 CJ7 Laredo, 33x9.5 BFG AT's, 'glass nose to tail in '00, 'New' frame,wires and plumbing in '09. Carter BBD Carbed 4.0 HO in '10. Some Canadian Bush Jeep Runs and Build Photos: http://mikeromainjeeptrips.shutterfly.com
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