Survey- For those with misfire issues

[DAVECS2]

If you replaced the camshaft it is good to do a cam relearn or resync. Chances are if the other cam had a problem or was worn the ECM adjust cam positioning to compensate, and now the new cam will be off

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[ShadowsPapa]

If you replaced the camshaft it is good to do a cam relearn or resync. Chances are if the other cam had a problem or was worn the ECM adjust cam positioning to compensate, and now the new cam will be off

There's been an issue with these where they just have "not learned" - they need to be told to learn CCDIFF.
Mine had no data, it hadn't learned CCDIFF. They forced a learn and life's been good.
Several of us have had issues with that. At first STAR was just having the dealership gather data and sending it to them, suggesting the learn process. Then they later came out with the TSB saying if this, then that - they nailed it down after receiving data on trucks like mine.

Yeah, if you replace a cam I'd see the learn as a given, a must do. In our cases - no cam was ever replaced. Stock as it arrived from the factory.

They say any time the cam, chain, or similar parts are replaced that be done.
But ours were stock systems, no new parts.
Mine did it with 50-some miles on it less than a week after picking it up new.

 

[DAVECS2]

If you replaced the camshaft it is good to do a cam relearn or resync. Chances are if the other cam had a problem or was worn the ECM adjust cam positioning to compensate, and now the new cam will be off

There's been an issue with these where they just have "not learned" - they need to be told to learn CCDIFF.
Mine had no data, it hadn't learned CCDIFF. They forced a learn and life's been good.
Several of us have had issues with that. At first STAR was just having the dealership gather data and sending it to them, suggesting the learn process. Then they later came out with the TSB saying if this, then that - they nailed it down after receiving data on trucks like mine.

Yeah, if you replace a cam I'd see the learn as a given, a must do. In our cases - no cam was ever replaced. Stock as it arrived from the factory.

They say any time the cam, chain, or similar parts are replaced that be done.
But ours were stock systems, no new parts.
Mine did it with 50-some miles on it less than a week after picking it up new.

There is a guy that posted just recently saying he replaced a bunch of stuff and still had issues, so it was directed at him.

Another thing I noticed with many of the calibrations I have looked at, they are using or copying a cam calibration position, that is generic and that could present problems from teyck to truck depending on how well they hold cam centerline from cam to cam and sensor to sensor. My guess is that "there is no data" actual means "the cam is so far from expected it never starts the learning process"

 

[Pion]

At just over 51000 miles I had a P0306 on my Launch Edition Gladiator this last weekend. After seeing that it'd take motor surgery to get to the spark plugs and coils I took it to the dealer that I was luckily near (was on a long road trip). They replaced the #6 coil and I had them replace all of the spark plugs since they were down there. Was able to drive it home with no issues. Unfortunately as my daughter was graduating college I had to leave it at the dealership and rent another vehicle to finish the trip and then picked up the truck on the way back.

 

[Snook]

Well, it finally happened again, almost a year since the second flashing CEL. (P0300) This time it came at 18000 miles, same exact scenario as the other two. Had driven the truck in the morning, came home and parked it for approx 20 minutes, left again and the CEL began to flash as I was driving away from the house (low speed). Only flashed briefly and went off, truck never ran rough (same as before). Parked again for about an hour and a half, got back in and drove home with no CEL at all.

Ive posted in this thread about the other two incidents. The last one was almost a year ago, took it to the dealer, they checked and cleared the code and sent me on my way saying that Stelantis engineering knows of the issue but had no fix at the time.

 

[BAT]

Well, it finally happened again, almost a year since the second flashing CEL. (P0300) This time it came at 18000 miles, same exact scenario as the other two. Had driven the truck in the morning, came home and parked it for approx 20 minutes, left again and the CEL began to flash as I was driving away from the house (low speed). Only flashed briefly and went off, truck never ran rough (same as before). Parked again for about an hour and a half, got back in and drove home with no CEL at all.

Ive posted in this thread about the other two incidents. The last one was almost a year ago, took it to the dealer, they checked and cleared the code and sent me on my way saying that Stelantis engineering knows of the issue but had no fix at the time.

I had similar just recently on a trip out of town. Stopped for about 15 minutes and then when driving down the road light on dash came on. Happened to have a jeep dealership very near by so I stopped in and they checked it and cleared the code. They said it was a misfire and could not find anything else. I have not had anything more pop up on it since then (About 1 month ago).

 

[Snook]

I had similar just recently on a trip out of town. Stopped for about 15 minutes and then when driving down the road light on dash came on. Happened to have a jeep dealership very near by so I stopped in and they checked it and cleared the code. They said it was a misfire and could not find anything else. I have not had anything more pop up on it since then (About 1 month ago).

Yes, that's what happens with mine. Did yours run rough when the CEL was flashing?

 

[ShadowsPapa]

Did you see my misfire issues, the criteria, symptoms, timing, and resolution?

I've posted these symptoms several times in the forums, along with the resolution that worked in my case.

First experience with misfire was Saturday 7-16-22, about 9:30am
Drove to Menards, was in there 5-10 minutes, left and went to Bass Pro
Was in Bass Pro about 30 minutes. When I came out the truck started and drove as normal for about 2 minutes then the CEL started to flash as I heard “dings”. This went on for ¼ mile or so (most of the Bass Pro frontage road) and then the flashing stopped, it dinged and the light set and stayed on.
This was at about 157 miles.
I used ESS (stop/start) as a diagnostic tool as it will not function if a list of conditions are not met and/or the engine has any malfunctions detected. After the cabin temp was reached auto stop/start said it was ready.
I reached a stop light and pressed the brake and the cluster said “auto stop/start not ready. When I let off the brake, it said it was ready again. When I pressed the brake at the next stop it said not ready.
I stopped at the bank and was inside about 5 minutes. I came out and the truck started and drove fine. MIL was still on but there were no “dings” and the auto stop/start worked perfectly, indicating that no engine issues were detected this session.
I got home and used some of my diagnostic software to reset the CEL.
I cleared codes but it had a “permanent” P0300 that would not clear. The MiL went off.

Weeks passed, took it to church, came out and it started fine and exited the parking lot fine but then started to misfire as I drove slowly through that small town with a lot of stop signs. Got to the north edge of town and by that time it was bucking badly. Launched JSCAN and monitored and found #2 wasn't firing much if at all based on the time I monitored, the RPM and the number of misfires.
Pay attention in algebra and college math classes, kids - you can do it, too. At 800 RPM it should fire every cylinder 400 times. RPM times number of minutes divided by 2.
So if it's misfiring for 2.5 (that's 2 and a half) minutes, running 750 RPM, each cylinder should fire about 927 times.
I timed mine for 3 minutes at idle RPM and got ->

The other cylinders on that bank misfired but in decreasing severity as far as numbers. It cleared up on its own after a few seconds and didn't do it again for weeks. In that case the MIL never stayed on.
Then we took it to Florida - and stopped at a rest area where it did it again, flashing MIL, beeps, for a very short time, didn't set the MIL if I recall correctly.

The pattern - if you drive until thoroughly warmed up and stop for a longer period – 15, 20, 30 or 40 minutes, it will start and run fine but after a short time it will misfire and set a DTC of P0300 and likely set the MIL however, the misfires after stops on our long trip didn't always set the MIL.

I'll bet they need to follow the TSB I posted.
Here it is again -

 

[Snook]

Did you see my misfire issues, the criteria, symptoms, timing, and resolution?

I've posted these symptoms several times in the forums, along with the resolution that worked in my case.

First experience with misfire was Saturday 7-16-22, about 9:30am
Drove to Menards, was in there 5-10 minutes, left and went to Bass Pro
Was in Bass Pro about 30 minutes. When I came out the truck started and drove as normal for about 2 minutes then the CEL started to flash as I heard “dings”. This went on for ¼ mile or so (most of the Bass Pro frontage road) and then the flashing stopped, it dinged and the light set and stayed on.
This was at about 157 miles.
I used ESS (stop/start) as a diagnostic tool as it will not function if a list of conditions are not met and/or the engine has any malfunctions detected. After the cabin temp was reached auto stop/start said it was ready.
I reached a stop light and pressed the brake and the cluster said “auto stop/start not ready. When I let off the brake, it said it was ready again. When I pressed the brake at the next stop it said not ready.
I stopped at the bank and was inside about 5 minutes. I came out and the truck started and drove fine. MIL was still on but there were no “dings” and the auto stop/start worked perfectly, indicating that no engine issues were detected this session.
I got home and used some of my diagnostic software to reset the CEL.
I cleared codes but it had a “permanent” P0300 that would not clear. The MiL went off.

Weeks passed, took it to church, came out and it started fine and exited the parking lot fine but then started to misfire as I drove slowly through that small town with a lot of stop signs. Got to the north edge of town and by that time it was bucking badly. Launched JSCAN and monitored and found #2 wasn't firing much if at all based on the time I monitored, the RPM and the number of misfires.
Pay attention in algebra and college math classes, kids - you can do it, too. At 800 RPM it should fire every cylinder 400 times. RPM times number of minutes divided by 2.
So if it's misfiring for 2.5 (that's 2 and a half) minutes, running 750 RPM, each cylinder should fire about 927 times.
I timed mine for 3 minutes at idle RPM and got ->

The other cylinders on that bank misfired but in decreasing severity as far as numbers. It cleared up on its own after a few seconds and didn't do it again for weeks. In that case the MIL never stayed on.
Then we took it to Florida - and stopped at a rest area where it did it again, flashing MIL, beeps, for a very short time, didn't set the MIL if I recall correctly.

The pattern - if you drive until thoroughly warmed up and stop for a longer period – 15, 20, 30 or 40 minutes, it will start and run fine but after a short time it will misfire and set a DTC of P0300 and likely set the MIL however, the misfires after stops on our long trip didn't always set the MIL.

I'll bet they need to follow the TSB I posted.
Here it is again -

you and I have had this discussion last time, our situations are almost identical. Im driving it today, and I'll schedule a service this week. There's no CEL right now so there might not be a stored code from yesterdays incident.

 

[BAT]

Yes, that's what happens with mine. Did yours run rough when the CEL was flashing?

No It ran fine. Just I was on a long road trip when it happened and I was going to an area where not a lot of mechanical assistance could be rendered (LOL).

 

[Snook]

No It ran fine. Just I was on a long road trip when it happened and I was going to an area where not a lot of mechanical assistance could be rendered (LOL).

My first occurrence was on a trip to Florida towing a boat.

 

[wachuko]

Hopefully this solves the issue for mine…

 

[Snook]

Hopefully this solves the issue for mine…

What did they do?

 

[wachuko]

What did they do?

Software update: Performed rapid response 08-071-22 Rev C Update PCM Software

I asked them to do the oil and filter change, along with tire rotation... It is free/part of the deal.

They supposedly changed the oil and rotated the tires... I doubt that they actually did this... I do not see a single trace of them doing so... They did not even perform the reset on the display nor adjusted the tire pressures! SOB!

This is why I have been doing all maintenance myself... F* it... Jeep has 11,000 miles and I have done three oil changes already... I was going to do the next one at 12K miles and figured, since it was there, to let them do it... Looks like I will be doing it anyway.

 

[Eeeckman]

Update: after two more visits to my dealer, they updated my software in June 2023 with a December 2022 update that addresses P0300. Fast forward to August while traveling through Canada, my CEL went crazy and engine started running super rough. Had to leave my Gladiator at the dealer in Canada. They determined an O2 sensor was contaminated with oil, likely from previous head work on cams and lifters. Fortunately, they covered the work under warranty. Jeep's running OK now, but seriously concerned there's something wrong with the engine causing oil migration to the exhaust and O2 sensor. I'm highly doubtful head work 8 months ago would lead to an O2 oil contamination issue now unless there's head gasket issues or other internal engine damage. ?

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