Misfiring on Cylinder 4 and 5

[LibertySport]

Replaced all 6 coils two days ago and changed the spark plugs 300 miles ago. Jeep ran great for two days after coil replacement. Now all the sudden around 3pm Jeep throws the codes P0304 (Cylinder 4 misfire), P0305 (Cylinder 5 misfire), and P0300 (Multiple cylinder misfire). I don't get it. Could two fuel injectors just need to be cleaned?

 

[uss2defiant]

First try:

switch coil #4 and #5 to a different location and see whether the problem follows.
If it does, change those coils.

 

[libertybob]

Coils...

Electronic parts suffer from infant failure. Happens early in the parts life. These two coils may be infant failures. As recommended, switch positions to see if the misfire follows. Probably not plugs as they have been good for 300 miles.

 

[LibertySport]

Still suffered the problem. Same thing rough idle and the bogging that follows with +2 coils going out. Going to AutoZone to exchange them. See if that will fix the problem. Annoyance is rising. First time I posted this it was my ignorance at fault. Now that I clearly had the issue fixed. Now it wants to mess up before a family trip. Also, it's only vehicle for now (rants over).

I'll let you know what happens after replacing coils 4 & 5.

Thanks for the help.

 

[profdlp]

Good luck to you.

 

[van462]

I've had issues with autozone coilpacks. Originally had a #5 cylinder misfire, swapped it with autozone coilpack. It would do OK until the rainy season came and faulted on number 5 again. Swapped it with another autozone coilpack worked great until i realized it was causing my front speakers to pop and hiss at idle. Picked an OEM coilpack up and no problems for a year now.

 

[uss2defiant]

napa sold ones are oem as well