Code P 0305

[dnm45227]

Well my '05 renegade is throwing this code. Appears to be missfire in cylinder 5. I pulled the negative cable cleared it, but it came back. Still runs fine though.

It has 26k on it. What are my chances of it just being a tune up? I've heard of a couple throwing this code and it ended up needing head work. Good thing we got the extended warranty.

Edit: Just for the record it happened while SHE was driving it.

 

[JeepJeepster]

That head work crap has me worried. I hope the 3.7 isnt a dud and starting failing on everyone around 100k. I know many people that tow and really beat on their libbys and the powertrain does just fine. But then there are those few thats had headwork. I think its only bad valve springs but you must take the heads off to get that done.

It could be as simple as a bad spark plug or coil. You could pop the #5 plug out and check it out. If its not the plug then I would go ahead and take it in and let them fix it, or screw it up even more. 8-[

 

[dnm45227]

I thouht about swaping the plug and coil pack from like 5-6 and seeing if the trouble code moves with it. That would nail it down for sure, but I'm lazy. Maybe next weekend.

I'll clear the code again, and drive it this week. If it comes back again I'll try the switch thing next weekend.

 

[Marlon_JB2]

That head work crap has me worried. I hope the 3.7 isnt a dud and starting failing on everyone around 100k. I know many people that tow and really beat on their libbys and the powertrain does just fine. But then there are those few thats had headwork. I think its only bad valve springs but you must take the heads off to get that done.

It could be as simple as a bad spark plug or coil. You could pop the #5 plug out and check it out. If its not the plug then I would go ahead and take it in and let them fix it, or screw it up even more. 8-[

Gee... you worry about every engine except the 4.0L...

The "head work crap" is isolated to '02 models and is NOT common.

26k? Oh yeah, it's time for a tune-up!

 

[dnm45227]

I agree with the tune up, like I confessed LAZY and CHEAP (won't pay someone to do it). However, a guy at work has an '05 sport w/about 25k and he just had to have head work done. It started with the exact same P 0305 trouble code too.

 

[alpnst]

26k? Oh yeah, it's time for a tune-up![/quote]

Where did you come up with the idea that a car needs a tune up after 26k miles. Mercedes says you don't need to change plugs for 100K. It was someting similar for my WJ Limited, maybe 75,000. If I had to do a tune up every 25,000 miles or so I would have never bought it.[/i]

 

[dnm45227]

Almost everybody here (if not all) says that thier plugs were toast when they chaged them at the 30 or 40k interval. I just assumed that DC got plugs under the same contract that they got lower ball joints and tires and would just change them before winter.

Personally, I usually change plugs when the car runs funny.

 

[JeepJeepster]

Plugs need to be changed at 30k in the libby. O

How about that guys 05 libby Marlon_JBT? The reason i do not worry about the 4.0 is b/c we have 2 one with 160k and one with 60k. Many people have them and have 0 issues with them. 8-[

 

[Dave]

If you are under warrenty as noted take it to the dealer and let them replace the coil pack and plug. I'm sure it will be fine. That coil pack probably has a minor occasional skip and is just causing the code.

 

[jfortier777]

How about that guys 05 libby Marlon_JBT? The reason i do not worry about the 4.0 is b/c we have 2 one with 160k and one with 60k. Many people have them and have 0 issues with them. 8-[

But they're poisoning the earth!!!!! NOOOOOOOOO!!!!!!

 

[DougBenn]

Here's the deal.

Been throught it. 05 Limited 21K miles

Bad valve springs. We had the P0305 for a long time before they figured it out.

5x back to the dealer. Flashed comps, etc Also changed plugs , coils, inputs and outputs on the comp to rule it out.

After they rebuilt the head it went away and never came back.

However one came in the day after mine left with holes in the valve cover , sucked a valve and valve springs were broken. Hmmm #5 cyl too.

Why is it #5 always? Don't know but share this info with your dealer and get it taken care of now.

http://jeepkj.com/forums/viewtopic.php?t=4121&highlight=0305+p0305

 

[Marlon_JB2]

Plugs need to be changed at 30k in the libby. O

How about that guys 05 libby Marlon_JBT? The reason i do not worry about the 4.0 is b/c we have 2 one with 160k and one with 60k. Many people have them and have 0 issues with them. 8-[

I take back what I said! First '05 I've heard of! Dangit.

So much for listening to that dealership tech. My 3.7L hadn't thrown an engine related code in 26k miles. Neither has my sister's in 20k. I miss that engine... just smooth and the immediate seat in pants feel.

What I want to know, is why I was driving next to a 3.7L Grand Cherokee, and heard that engine over my 2.8L... hmm...

Anyway, I guess I just get sick and tired of all the Liberty bashing, even from the owners. It's getting really old. :-s No offense to you.

 

[Marlon_JB2]

26k? Oh yeah, it's time for a tune-up!

Where did you come up with the idea that a car needs a tune up after 26k miles. Mercedes says you don't need to change plugs for 100K. It was someting similar for my WJ Limited, maybe 75,000. If I had to do a tune up every 25,000 miles or so I would have never bought it.[/i]

You should have seen my spark plugs and gas consumption after 19k miles.

 

[MoladoGuy]

I did a tune up at 40K. Thank god I did!! Boy did it run ever so sweet. My spark plugs were dark and I should've done the tune up 10K prior.

If your not looking to do a tune up, or swear that it won't help, then do it anyway for the peace of mind. At least you know your stuff is up to date, even if you are still throwing codes.

 

[DougBenn]

As a side note, my other Libby has had 0 problems to date. Engine is a little loud but no issues. 31K so far.