I would first check the wire harness for rodent wire chewing. the swap the coil with another cylinder coil and see if the misfire stays at cyl 3 or to the coil you swapped it with

 

We did that as well we moved all the coils around same one and we replaced the wire for cylinder misfiring

 

Hi @jacksonemily03 ,

Welcome to the Forum and sorry to hear about your Cherokee issue:

1. When you mean you replaced the wire, do you mean you cut/soldered a new wire length and/or connector on? Note, you cannot 'swap' the wire that connects to one coil on one cyl. with another. That would absolutely cause a misfire. Each wire must go to its pre-assigned coil pack. When you examined the wire, any evidence of fraying, insulation being worn etc.?

2. I noticed on your Sales order you have the 2.4 engine. This could also just be an issue with the "brick" inside the 2.4 MultiAir engine. It uses a oil pressure-fired solenoid to open the intake valve. If the solenoid in cyl 3 is defective or say, oil debris was caught in the passage of the MultiAir unit of cyl 3, it would not fire to open the intake valve causing a misfire. Quesiton...is this the only code or were there additional ones? Unfortunately, the solenoids in the MultiAir unit (called the "brick") cannot be replaced individually. The resolution is to replace the brick assembly.

3. Your 2.4 doesn't have a conventional camshaft for the intake so it's unlikely you have any camshaft or similar issues going on however, you mentioned you cleaned your injector. How did you do this? Do you mean injector cleaner in the fuel tank? If so, I would try swapping the #3 injector with either 1, 2 or 4 and see if the problem travels. If so, the injector is bad and needs to be replaced. Note, injector cleaner takes time to clean injectors chemically so if it's already clogged this method may not work. The injector may be more likely, failing electrically (and injector cleaner wouldn't help an electrically failing injector ). Another option before moving injectors is to Ohm them out. If #3 has an Ohm reading wayyy different than 1, 2 or 4, there's your problem.

4. Lastly (fair warning), a misfire can always be the result of low cylinder compression which is can indicate a serious leak condition in a cylinder. This usually isn't the case unless something else happened e.g. ran without sufficient oil or coolant and engine overheated or vehicle was ridden "hard". It's not a common issue but as a full disclosure, I'm mentioning it. If you examine your coolant in the bottle, do you see any evidence of oil mixing (e.g. an oily sheen). If you check the oil on your dipstick, does it look like normal oil or does it have a brown "milkshake" look to it? Any white or blue smoke from the exhaust pipe? These are symptoms of a cylinder problem. However for now, I'd focus on the the common things for the 2.4 engine.. the injector and brick to resolve this.

 

Note one more thing... The O2 sensor and catalytic converter are "global" across all four cylinders in the engine. Any problem with either of these would unlikely trigger a code specific to cylinder 3 (or any other specific cylinder).

 

We did do all the things you mentioned also I check the oil this morning it was normal. The car hasn’t over heated and I think I did need a o2 sensor because the car did lag in Accelerating… we pulled out the injector and sprayed it with cleaner we swapped it and still same issue the reading above was after we did all of those things..

 

We did do all the things you mentioned also I check the oil this morning it was normal. The car hasn’t over heated and I think I did need a o2 sensor because the car did lag in Accelerating… we pulled out the injector and sprayed it with cleaner we swapped it and still same issue the reading above was after we did all of those things..

Hi,

• Re: #1 above, you didn't respond why you replaced the wire. Was there obvious damage?

• Note, spraying an injector (across its face with cleaner) really doesn't do much as clogs form on the sending (inner) side from contaminants in the gas. However, if you swapped it to a different cylinder and it was the same code, then that would rule out the injector. When you swapped it, you took its o-rings along with it, correct? (leaking o-rings can let unmetered air in causing a misfire). And you Ohm eveything out, right? (I'm assuming you did since you said you did all those things)

Sounds like your next diagnostic point is the brick then. Note, I wouldn't spend a lot of time tracking down laggy acceleration. A misfiring cylinder (when there's only 4 to begin with) can account for that. I'd look for the problem first and then see if the symptoms clear up.