Misfire on cylinders 1, 3, and 5 on 2012 Jeep Wrangler JK

jszeinstra

New Member
Joined
Oct 1, 2021
Messages
3
Location
Grand Rapids MI
New to the forum. Had a 2007 jk loved it drove it 150k miles and loved it but I wanted a stick..... and then traded for a 2012. Had a nagging issue ever since I got it in the spring. stock 108 k miles.

Check engine, throwing bank 1 too rich and lots of Missfires on 1 3 5 Found another post in here with the same exact issue and same steps so far but did not put a solution. Leaning toward wiring issue.

What I've tried so far:
- New Spark Plugs:
-Checked Coils, and swapped all look good
- New O2 Sensors (all 4 - both sides)
- New Crankshaft Position Sensor
- New MAP Sensor

- New Camshaft Position Sensor
- New Injector on Cyl 1 = No change still misfiring
- New upper and lower o-rings for injectors
- New upper and lower o-rings for Lower and Upper Manifolds


Cleaned the main wiring harness on the top, reseated the PCM and don't see anything major but my guess is it is a manufacturing issue and someone else out there has the same rubbing wire....



Checked Cat for plug with a pressure gauge, checked compression on all 3 and good. cleared PCM and the issue will come and go at random.


Leaning towards a wiring issue and will look one more time at the injector rail and the harness along there. Made an appointment with a local shop as well in 2 weeks, but in the meantime might take a look again at it. Also don't want to throw anything more at it without really knowing the issue.

Thanks. Love my jeep.... She'll get fixed someday lol

Jason
 
the connector for the O2 on the passenger side? or a connector harness up top. tcleaned and checked the big main connector on the very top but did not find any other connectors that control the harness for the injectors/coils.

Thanks


Jason