[Vampire]

Looking for other easy things to find on my jeep before I go the expensive route of dealership.

The story I have a misfire on cylinder 5. This only happens when the jeep is started with the auto start and she is left to idle for 10 minutes. I have changed the plug and the injector on 5 cleared the code ran her for a straight hour at 70+ mph. I have no loss of power and no sputtering or hard starting. The next day I used the auto start again started fine ran for 10+ minutes and the CEL came back. Again no loss of power sputtering or hard starting. Is there anything else that a home mechanic could look at that would be fairly easy to check? Took it in got code read again and its still p0305. Is there anyway I am dealing with a historic code that comes back when its warming up in the Minnesota Winter? Do I have them clear the historical code and see if it comes back? Thanks for any and all advice it is appreciated!

Also can I get verification of the Cylinder 5 location?

Motor |1 3 5
Front |2 4 6
===============
Front of Jeep

I really don't want to spend 500.00+ on repairs if I don't have too.

Sorry for the double post I placed the original in the wrong forum location and have removed its contents.

 

[BlackHawk2016]

From what I have found for the Pentastar V6 is #1 cyl is on the right bank (You listed on left bank) so #5 cyl would be opposite from what you are thinking so new plug and injector are on wrong cyl. Anyone else out there verify this.

Firing order 1-2-3-4-5-6; lead cylinder is #1 in the right bank

 

[MKR_DmD]

Firing order 1-2-3-4-5-6; lead cylinder is #1 in the right bank

That firing order is wrong. I don't know what it is suppose to be, but the cylinders do not go in order like that. If they did your engine would be shaking like crazy. They probably go like, 1-6-2-5-3-4.


I cannot find anything with the cylinder layout. This is what I did on my old car to test the cylinder. Clear your codes. Disconnect the spark plug coil from cylinder 5, start the car, let run 5 seconds and shut off. Check your CEL and see if it says cylinder 5 misfire. If it is another cylinder, then you guess wrong. Clear codes and start again.

 

[Mark_]

Firing order for the 3.6L (1-2-3-4-5-6) is defined here : http://www.pentastars.com/engines/specifications.php
http://forum.chryslerminivan.net/sh...-ltr.-VVT-2-cylinder-location-on-2012-T-amp-C
Post #2 in next thread says that #1 is indeed right bank (3.6L) : http://forum.chryslerminivan.net/sh...-ltr.-VVT-2-cylinder-location-on-2012-T-amp-C

So #5 would in fact be the one closest to the driver's seat (back right when standing in front of the Jeep).

Just FYI : we had a member very recently with a misfire code and the dealership ended up fixing it with a new coil (plug was fine, injector also). These engines have coil over plugs, so 6 individual coils. Not too expensive. Rock Auto has them.

Linky to recent misfire thread (for guidance) : http://jeepcherokeeclub.com/4-2014-...5585-service-department-aneurysm-venting.html

Good luck.

 

[Vampire]

So then we did replace the correct one. Dammit I was hoping I was slightly wrong there. We replaced the plug and coil. 12 bucks for the plug and 24 for the coil.

 

[Bill837]

Before buying one, I would simply swap the coil to another cylinder, clear the codes and run it until I got the code again and see if it moved with the coil.

 

[Vampire]

Before buying one, I would simply swap the coil to another cylinder, clear the codes and run it until I got the code again and see if it moved with the coil.

We replaced both at the time of the intended fix. Looks like I will have to take her in and pony up the cash. Thanks everyone for the help and confirmation of piston layouts.

 

[Vampire]

Took it in got only half of the compression on cylinder 5 as on the other cylinders. They said they need to replace the CAM to fix it. Good news its covered!

 

[Mark_]

Took it in got only half of the compression on cylinder 5 as on the other cylinders. They said they need to replace the CAM to fix it. Good news its covered!

Yikes !

Thanks for the follow-up... and yeah, you sure want that covered under warranty...:wink:

 

[michaeldelaney0515]

We replaced both at the time of the intended fix. Looks like I will have to take her in and pony up the cash. Thanks everyone for the help and confirmation of piston layouts.

It's the pcv valve that is on the valve cover above the 5th cylinder if the seal is damaged it will cause this misfire. Its comonly damaged by people no knowing it has to be removed to get valve cover off

 

[Mark_]

It's the pcv valve that is on the valve cover above the 5th cylinder if the seal is damaged it will cause this misfire. Its comonly damaged by people no knowing it has to be removed to get valve cover off

With 50% compression on cyl 5 ?

 

[Rob_fall]

It's the pcv valve that is on the valve cover above the 5th cylinder if the seal is damaged it will cause this misfire. Its comonly damaged by people no knowing it has to be removed to get valve cover off

I'm wondering if PCV can case oil to push thru valve cover spark plug hole seals like an old style PCV being clogged or bad??

 

[Gary Kline]

I'm wondering if PCV can case oil to push thru valve cover spark plug hole seals like an old style PCV being clogged or bad??

I'm having a hard time wrapping my head around why a bad PCV valve (or seal) would be causing a specific cylinder misfire? While the PCV valve is located next to cyl 5, that's just it's physical location. It's not interacting with cyl/spark plug #5 or either the intake or exhaust #5 valves etc. And the hose on the valve exit just leads back to the common air intake manifold, again, not cylinder-specific.