3.6 Pentastar Misfire on Cylinders 1, 3, & 5

Talk about resurrecting an old thread. Holy crap! If I was OP, I would've given up halfway through that insane and costly process, and sold it.

@Roam8 lucky you, you got yours solved. đź‘Ť
 
WestCoastDan said:
Given the description of the issue and the solution provided, I think a vacuum leak under the intake is a great possibility, but how would that have caused all 3 cylinders to be so lean instead of only 1 of them?
Was there any evidence of a failed seal (pinched, damaged, etc.) on the injectors?

Just trying to picture where the failure was that could have affected all 3 cylinders.
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To much unburnt oxygen passing the Bank's O2 Sensor will have the PCM enriching the mix on all cylinders... doesnt matter if the source of O2 is a single cylinder or all 3...

I can't say either way because we didn't replace them one at a time...

Our lead shotgunned 3 new injectors on a whim and it worked like a charm..

So I was just passing the info along... Especially since swapping injector banks is not something OP had tried ..
 
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My 2015 had camshafts replaced and now it’s throwing a P0300 code. Thrown a few parts at it try to figure it out. J scan shows that cylinders two four and six are missing. Live data shows that it’s only missing at idle. It starts runs and drives fine. It’s going to a different shop Thursday to try to chase down that issue. They went to the shop for a valve cover gasket. Leak had no prior codes no other issues whatsoever. Now it’s doing this. I’ve read every page on this thread and it seems like lots of people are having the same issues. Hopefully the new mechanic figures it out quickly. It’s been in the shop for three months almost 4. I’m tired of making payments on something I can’t drive lol!
 
Sounds to me like fiddling with the wire harness to swap the valve cover gasket has exposed a few poor connections and/or failing connectors.
 
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WestCoastDan said:
Sounds to me like fiddling with the wire harness to swap the valve cover gasket has exposed a few poor connections and/or failing connectors.
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I just got done reading some of your other posts about that! I’ll pass that information on to my mechanic! Thanks! Secondary question will it hurt it to keep driving it?
 
Jhiero said:
I just got done reading some of your other posts about that! I’ll pass that information on to my mechanic! Thanks! Secondary question will it hurt it to keep driving it?
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Depends on what the root cause actually is… your vehicle; you decide.

Good luck on tracking it down.
 
WestCoastDan said:
Sounds to me like fiddling with the wire harness to swap the valve cover gasket has exposed a few poor connections and/or failing connectors.
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Update::: just got a call from the new mechanic. He’s had it for two weeks. He’s tore it down checked timing and camshafts and everything the original mechanic fixed. Put it back together. Did leakage tests. Compression tests. Ran every test on it that he knew to run. He says he’s traced every wire and connector. He’s checked every hose. He’s checked every every reconnection everything. He says that he can’t find one single thing that would be causing a misfire. He’s not charging me anything. He just said come get it. I’m done with it. He did mention something about the cylinder head. Which I’ve read on here to about a cylinder head issue. Where do I go from here guys? It’s been four months since I’ve been able to drive my Jeep. Making payments on it for it at the mechanics car lot. Do I just have him go ahead and replace the head? And hope that fixes it. Or do I get a third opinion
 
I may have gotten lucky with the root cause being the wire harness issue… but I didn’t find that issue until after I had repaired the tick in the right head, replaced TIPM, coil packs, plugs, and tested the ECU.
 
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Jhiero said:
Ran every test on it that he knew to run.
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Jhiero said:
He did mention something about the cylinder head. Which I’ve read on here to about a cylinder head issue.
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Did he run a leak down test? The primary cylinder head issue is high valve seat recession on the driver's side head. If this is advanced enough to cause an issue the leak-down test would show it.
 
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