get a can of carb cleaner, brake clean, or starting fluid, and with the jeep running,... spray in the suspected areas where a vacuum leak could be present. If the motor stumbles, idles differently, then you found your leak.
EDIT: P0455 is not a lean code
P0455: Evap emissions control system Large Leak Detected
Check your gas cap,.. if thats on tight, check the rubber lines from the the evap purge solenoid, to the evap canister, etc. you might want to take it to a shop so they can smoke the system and check for leaks
Last edited by Mattpar; 03-30-2010 at 11:27 PM.