# 2001 Jeep Cherokee Misfire **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** cherokee, jeep, misfire\ **Created:** [December 3, 2009, 7:37am UTC](https://community.cartalk.com/t/2001-jeep-cherokee-misfire/40295 "2009-12-03T07:37:04Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![lee57103](https://avatars.discourse-cdn.com/v4/letter/l/9de0a6/32.png) [@lee57103](https://community.cartalk.com/u/lee57103)\ **Post date:** [December 3, 2009, 7:37am UTC](https://community.cartalk.com/t/2001-jeep-cherokee-misfire/40295/1 "2009-12-03T07:37:04Z")
I have a 2001 Jeep Cherokee with 97k miles. The engine keeps misfire in cylinder 6 when going into high rev(overtaking cars on interstate). I have replaced the ignition coil pack and the fuel injector and replaced all 6 spark plugs 2 months ago. I really don’t know what else would cause a misfire. ---
**Author:** ![cigroller](https://avatars.discourse-cdn.com/v4/letter/c/c68b51/32.png) [@cigroller](https://community.cartalk.com/u/cigroller)\ **Post date:** [December 3, 2009, 12:21pm UTC](https://community.cartalk.com/t/2001-jeep-cherokee-misfire/40295/2 "2009-12-03T12:21:19Z")
“ignition coil pack and the fuel injector and replaced all 6 spark plugs” - spark plug wires? Presumably you have a code - something like P0306? Any other codes? Check the compression - look esp. at #6 I’d get a new fuel filter on it and check the fuel pressure under load - preferably with a gauge hooked up while driving. ---
**Author:** ![lee57103](https://avatars.discourse-cdn.com/v4/letter/l/9de0a6/32.png) [@lee57103](https://community.cartalk.com/u/lee57103)\ **Post date:** [December 6, 2009, 8:18am UTC](https://community.cartalk.com/t/2001-jeep-cherokee-misfire/40295/3 "2009-12-06T08:18:12Z")
There is no spark plug wires, cap, rotor on this 4.0 6 cylinder. Ignition system is a coil pack that stretches the across all 6 spark plugs. From what I am seeing there is no fuel filter underneath the jeep in the frame rail like older Cherokees. I am assuming the filter is stuck in the fuel tank along the fuel pick-up. the fault code is p306 and I also failed to mention there is a rough idle. ---
**Author:** ![americar](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/americar/32/42_2.png) [@americar](https://community.cartalk.com/u/americar)\ **Post date:** [December 6, 2009, 1:17pm UTC](https://community.cartalk.com/t/2001-jeep-cherokee-misfire/40295/4 "2009-12-06T13:17:03Z")
Perform a compression test. ---
**Author:** ![newpony](https://avatars.discourse-cdn.com/v4/letter/n/41988e/32.png) [@newpony](https://community.cartalk.com/u/newpony)\ **Post date:** [December 6, 2009, 2:09pm UTC](https://community.cartalk.com/t/2001-jeep-cherokee-misfire/40295/5 "2009-12-06T14:09:09Z")
So, without details on code 306, is the injector dirty or clogged? Could also be any number of aggravating sensors that tell your coil packs when to fire; or even a vacuum leak. Just a few thoughts. ---
**Author:** ![oldtimer-11](https://avatars.discourse-cdn.com/v4/letter/o/e79b87/32.png) [@oldtimer-11](https://community.cartalk.com/u/oldtimer-11)\ **Post date:** [December 6, 2009, 2:20pm UTC](https://community.cartalk.com/t/2001-jeep-cherokee-misfire/40295/6 "2009-12-06T14:20:11Z")
pull the # 6 spark plug and 2 others, compare the plugs. Is number 6 black and wet looking-oil fouling, is it dry and black- carbon- could be caused by the misfire, or is it the color of your antifreeze- head gasket, cracked head or block, or in some cases-bad intake manifold or gasket.