Misfire detected Cyl 5 - not flashing

[KJ604]

Got my first cel today. OBD reader was already plugged in so I got to pull the code right away. Misfire detected cyl 5. I wasnt in the vehicle when the CEL came on. It was idling running and I was out of it. When I got back in the light was lit up but it was not flashing. I managed to get the code cleared and it didnt return for the rest of the drive home.

Should I start with spark plugs?

 

[ltd02]

How old are the plugs and what kind? I'd start by waiting to see if the code comes back.

 

[KJ604]

no idea what kind of plugs are in it, Ive only owned it for 7000kms

 

[ltd02]

no idea what kind of plugs are in it, Ive only owned it for 7000kms

I'd definitely pull at least one and see what you are working with. Might as well have a look at #5. OEM style copper cores are only good for about 20-30k (miles).

 

[belvedere]

I would only install standard NGKs. They work well in the Libby.

 

[uss2defiant]

switch the coil with another one and see whether the problem follows.
if so, bad coil or some connections issue.
If not could be bad spark plug.

 

[LibertyTC]

I always would start with the plug especially not knowing how old or what brand.
The gaps get eaten over time as well.
I replace mine every 25k miles and it is not that difficult to replace them yourself.
How 2 Video: https://www.youtube.com/watch?v=DxsEOCqhHx8&list=PLJqR66Id8eeeGrrrkZKlkbQqHBWRFycPg&index=66
The correct plug as listed under the hood is NGK ZFR6F-11G and gap is .040 inch.
You could even use some compressed air on the coil pack connector and give it a blast with a compressed air can.
By all means you can also move the coil pack & then see if code moves to a different cylinder, indicating the coil or connector issue.
Sometimes a dirty injector can cause a misfire. Use Chevron with Techron fuels wherever possible, and consider an injector cleaner at hwy speeds in the fuel.
I am overdue for a fuel rail/ pro induction/emission injector & intake cleaning soon as well.

 

[teeje]

The 3.7s were known for bad valve seats. Let us know what you find out. Before I put my brand new engine in, my old one had a misfire that came randomly. Seemed to fix it with some marvel mystery oil in the tank and I used some seafoam. Check your spark plugs (while you're checking you may as well replace them) and switch coil packs around and see what you get. But like I said, the 3.7s were known for bad valve seats. Marvel mystery oil and seafoam may do the trick.


Sent from my iPhone using Tapatalk

 

[Hockeygoon]

I always would start with the plug especially not knowing how old or what brand.
The gaps get eaten over time as well.

Agreed. If you don't know I would start with maintenance at ground 0 and assume nothing has been done. The first weekend I owned my Liberty I changed the engine oil, air filter, transfer case, differentials and had the transmission flushed. Did the same with my Bronco. Difference is my Bronco runs like a top and the Liberty is getting its 4th engine in 7 months.

 

[belvedere]

the liberty is getting its 4th engine in 7 months.

wtf???

 

[KJ604]

new plugs and coil packs installed today. WOW, what a difference! I dont know about mileage yet, but start up is WAY smoother, idle is smoother, lighter on the gas pedal to get her moving on the low end. all 6 plugs were considerably worn down. glad i finally caught a break in the weather to get her done

 

[twowings]

Agreed. If you don't know I would start with maintenance at ground 0 and assume nothing has been done. The first weekend I owned my Liberty I changed the engine oil, air filter, transfer case, differentials and had the transmission flushed. Did the same with my Bronco. Difference is my Bronco runs like a top and the Liberty is getting its 4th engine in 7 months.

Amen! Even if you bought it from Mother Teresa herself, treat EVERY used vehicle as if you found it as an orphan in the woods and change all fluids, check plug wear and gap, battery and connections, vacuum lines, thermostat, hoses, brake pads/shoes, and filters...no matter what the PO claims is "new"...in my 52 years of working on cars, owner's memories of "new" have a huge range....

 

[Winston Smith]

Agreed. If you don't know I would start with maintenance at ground 0 and assume nothing has been done. The first weekend I owned my Liberty I changed the engine oil, air filter, transfer case, differentials and had the transmission flushed. Did the same with my Bronco. Difference is my Bronco runs like a top and the Liberty is getting its 4th engine in 7 months.

Care to explain? Are you running them without any oil? :icon_lol:

 

[Hockeygoon]

Care to explain? Are you running them without any oil? :icon_lol:

The original engine ran great except with every oil change I was getting more metal flakes in the oil. I bought it with 65K and talked to the previous owner (older woman that traded it in for a new Escape) and she had no issues with it. First oil change no metal - the last oil change at 83K had quite a bit. Brought it in hoping it was only a timing chain issue of some kind. Shop pulled it apart and showed me the engine - all the rod bearings were wiped out - the rest of the engine looked remarkably clean for 83K with very little carbon. The shop theorized one of two things - the factory over torqued the rod caps or there was an obstruction in an oil passage. The shop owner said they could give it a "quick" rebuild by polishing the crank, new bearings and re-ring it, the mechanic actually working on it advised against it. I really wish I had done that and then sold the POS.

I bought a used engine (95K) with a warranty to drop in, fired it up and it was only hitting on 5, pulled a valve cover and a rocker arm was broke off and it was full of sludge. Salvage yard gave me credit towards a rebuild from Advanced Powertrain Solutions. Put it in and changed the oil at 500 miles and it was horrible with metal - figured it was break in material and changed it again at 2500 miles - even more metal than the original engine had been putting out. Filed a warranty claim and they kept putting me off - claiming they needed more than pictures and my say so that the oil had metal in it. Drove it another 2500 miles and had the original shop change the oil - full of metal and they noticed the valve train chattering. APS told them to pull the timing chain cover and they found nothing. APS shipped another engine and the shop installed it. Now they refuse the honor the labor part of the warranty claiming they see nothing wrong with the engine.

Right now the POS is sitting at home waiting for the weekend to install a new starter. Want to buy a Jeep with 91K miles and a new engine?

 

[LibertyTC]

new plugs and coil packs installed today. WOW, what a difference! I dont know about mileage yet, but start up is WAY smoother, idle is smoother, lighter on the gas pedal to get her moving on the low end. all 6 plugs were considerably worn down. glad i finally caught a break in the weather to get her done

Glad to hear your Kj is happy again! I recently replaced my coil packs too!
Seems like a jump in power right off the line.:gr_grin:
These coil pack hit the plugs hard with high volts! Good idea to change the plugs every 40,000 km.

 

[KJ604]

Glad to hear your Kj is happy again! I recently replaced my coil packs too!
Seems like a jump in power right off the line.:gr_grin:
These coil pack hit the plugs hard with high volts! Good idea to change the plugs every 40,000 km.

Yes! the first time I just pulled out of my driveway I noticed I needed less throttle to get her going! And Im pretty sure the plugs that came out of her were the originals on the vehicle, they did not look pretty. Id say 40,000 Kms is a good number for plugs, and Id say 100,000 kms for coil packs.

 

[Hockeygoon]

Yes! the first time I just pulled out of my driveway I noticed I needed less throttle to get her going! And Im pretty sure the plugs that came out of her were the originals on the vehicle, they did not look pretty. Id say 40,000 Kms is a good number for plugs, and Id say 100,000 kms for coil packs.

If you keep the plugs "fresh" the coil packs will last longer. Worn plugs with burned electrodes make the coil packs work harder shortening their lives. I don't know what Dodge uses for coil packs but I know Ford's will last a couple hundred thousand miles on the 4.6 and 5.4 engines.

 

[twowings]

I always wonder if the hotshoes who post here "I NEED more power!" and can't wait to spend their cash on cold-air-intake-throttle-body-spacer-loud-exhaust-cat-delete-octane-boosted-jet-chipped gooeyness have ever just tried simple recommended maintenance instead...:shrug: