The Jeep Wrangler was initially developed by AMC as a replacement for the the Jeep CJ-5 and CJ-7. Four Jeep Wrangler models were manufactured by AMC and later by its acquisitor, Chrysler. Troubleshooting a rough-idling Jeep Wrangler is within the skill-set of the average home mechanic.
Check for misadjusted carburetors. Older Wrangler models came with one- and two-barrel carburetors. Clogged jets, or a stuck choke will cause the Jeep to idle roughly. Be sure to check that the fuel filter is not clogged.
Check the fuel injection system. On newer Jeeps with fuel injection, low fuel pressure, and clogged injectors cause rough idling and hesitation when driving.
Fouled spark plug or cracked spark plug wires can cause idling issues. Check the timing of the engine to ensure the cylinders are firing in the proper order and sequence.
Worn, damaged or cracked vacuum hoses prevent the engine from idling or running properly. Replace any of these hoses.
