05 Liberty Renegade Misfire

[mk_v]

I thought I might try to get some insight into a problem I am having with my jeep liberty. A month or so ago I got a misfire code for the 6th cylinder. I checked for vacuums, fuel pressure, and made sure the wires weren't damaged. Everything checked out, so I reset the code. Everything was fine and dandy until this last weekend, I got a the p0300 multiple misfire code. I don't drive the jeep much except when in the woods so there was maybe 100 miles at most between the two error codes. The jeep runs fine and didn't have any noticeable loss of power. The Liberty has 76k on it. I am wondering if I should be looking at replacing all of the ignition coils? Any suggestions as to what I might look at? Any help would be great.

Thanks

 

[mk_v]

oh one other thing, I did check the spark plugs and their gap. I replaced the spark plugs within the last 2,000 miles

 

[nullptr]

There are a ton of things that can cause that error, which is basically, "Multiple random misfires detected" (p030# is a misfire code, where the last digit is the cylinder, with 0 being, "multiple").

Could be a dirty throttle body, or a clogged injector, or a clogged fuel pump, or any multitude of bad sensors, perhaps a broken vacuum line, or maybe the engine is about to explode. It's about the most useless generic error code ever.

Check the simple things first, make sure there are no broken vacuum lines or cables disconnected, then go from there.

 

[Billwill]

oh one other thing, I did check the spark plugs and their gap. I replaced the spark plugs within the last 2,000 miles

What type of plugs did you put in?

 

[mk_v]

What type of plugs did you put in?

Same as the factory plugs bought then at the jeep dealer.


Sent from my iPhone using Tapatalk

 

[renegade 04]

did you gap the spark plugs before you put them in as per the gap size on the sticker on your radiator support?

 

[CalcityRenegade]

Did you have the coil pack tested? I had coil pack issues when I bought my Renegade and took them to my local part store who was able to test them and tell me which ones were bad.

 

[mk_v]

did you gap the spark plugs before you put them in as per the gap size on the sticker on your radiator support?

I did gap them and when I pulled them I double checked to see if I did anything wrong. But it was all to specs


Sent from my iPhone using Tapatalk

 

[mk_v]

Did you have the coil pack tested? I had coil pack issues when I bought my Renegade and took them to my local part store who was able to test them and tell me which ones were bad.

I'll try that and see


Sent from my iPhone using Tapatalk

 

[CalcityRenegade]

I'll try that and see


Sent from my iPhone using Tapatalk

That would be my bet! Hopefully it fixes your issue.

 

[mk_v]

That would be my bet! Hopefully it fixes your issue.

Thank you for the insight. I really appreciate it.

Anyone know if I should stick with the mopar coil pack or would a Napa or autozone part be ok? Whichever would be best


Sent from my iPhone using Tapatalk

 

[uss2defiant]

the ones I bought from NAPA were the same manuf. as MOPAR's according to the guy at the store. He based it off a sticker on the part that indicating it.

I have one new from NAPA and one new one from autozone. Both running fine. the only thing I've found is the connector of the autozone was a little bit off tolerance for a pretty tight fit.

 

[mk_v]

the ones I bought from NAPA were the same manuf. as MOPAR's according to the guy at the store. He based it off a sticker on the part that indicating it.

I have one new from NAPA and one new one from autozone. Both running fine. the only thing I've found is the connector of the autozone was a little bit off tolerance for a pretty tight fit.

Thank you for the reply. I really appreciate the help. The mopar coils are $7 more than Napa so I think I might just get the mopar part. I was planning on just replacing them all so none of the others fail


Sent from my iPhone using Tapatalk

 

[CalcityRenegade]

I went aftermarket because of price up here, Have help up fine but one was replaced under warranty no problem, I would replace them all and have the rest tested and hold onto any good ones for spares along with a ratchet and 10mm socket in the hatch just in case haha

 

[mk_v]

I went aftermarket because of price up here, Have help up fine but one was replaced under warranty no problem, I would replace them all and have the rest tested and hold onto any good ones for spares along with a ratchet and 10mm socket in the hatch just in case haha

Haha good idea!


Sent from my iPhone using Tapatalk

 

[uss2defiant]

Your money your call.
I guess if you don't want to spend that extra ~$50 on something else.

 

[belvedere]

I don't drive the jeep much except when in the woods so there was maybe 100 miles at most between the two error codes.

This statement kinda caught my attention. "In the woods"...can I assume mostly low RPM driving? These engines can get carboned up easily, which can cause misfires due to valve deposits. They enjoy a little hard running. Since my wife mainly drives ours back and forth to work, once in a while I take out, get it good and warmed up, then run it hard through the gears. Even better to run some good, strong fuel system cleaner through while you do this.

 

[mk_v]

This statement kinda caught my attention. "In the woods"...can I assume mostly low RPM driving? These engines can get carboned up easily, which can cause misfires due to valve deposits. They enjoy a little hard running. Since my wife mainly drives ours back and forth to work, once in a while I take out, get it good and warmed up, then run it hard through the gears. Even better to run some good, strong fuel system cleaner through while you do this.

Your assumption is correct.
I was thinking about doing that the next time I fuel up, also I was reading about using the mopar combustion chamber cleaner. Has any body used that?


Sent from my iPhone using Tapatalk

 

[mx3_ryder]

Thank you for the reply. I really appreciate the help. The mopar coils are $7 more than Napa so I think I might just get the mopar part. I was planning on just replacing them all so none of the others fail


Sent from my iPhone using Tapatalk

I have 12 good spare coils if you're looking for a set?

 

[mk_v]

I have 12 good spare coils if you're looking for a set?

Thanks for the offer but I already ordered them


Sent from my iPhone using Tapatalk