If your Jeep is not running as smooth as it once did, it may be time for a tune - up Omix has all the necessary high - quality parts to restore the performance to your engine - parts built to meet or exceed factory standards. This ignition tune - up kit fits 97 - 98 Cherokee XJ 4.0 liter models and includes new oil filter, air filter, ignition wire set, distributor cap, rotor and spark plug set.