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I will attempt to organize what I believe to be the problem in this single post in an attempt to hopefully help others experiencing this to understand what's going on. But also, that if Dodge is reading this that perhaps they can understand, diagnose and fix this annoying issue.

There are countless threads on this problem. Many of them with stupid low miles on the car and a CEL that comes on shortly after they take delivery of the vehicle. This actually makes perfect sense when you understand the nature of the problem as I have discovered through experimenting with my car. What I am not 100% certain on is if this is exclusive to the 392 or not. I believe that it is, but I would have to go back through the countless threads to see if it crosses over to the RT or V6 models. But I am reasonably certain this issue is a 392 issue, which technically makes it an SRT issue, not Dodge. Although I suspect we can argue about the divisions and who owns what.

In any event, back to the issue at hand. The CEL comes on and you discover that your car has a P0300 error often times accompanied by a stored P0307. The P0300 is a random misfire and the P0307 is a misfire specific to the 7th cylinder. Although you won't always have the P0307. Sometimes it won't have a cylinder specific event and sometimes it may be another cylinder being identified. The CEL comes on when there are too many of these misfires relative to the number of engine crank revolutions. What is the exact ratio? I have no damn clue...

Now what is the source of the misfire you ask? When you cold start the car (that means the car has cooled off to ambient temperature not winter cold....) The car does what all cars do and that is it high idles for a period of time in an attempt to rapidly raise the engine to operating temperature. It is during this high idle period where the engine is missing. I personally test drove 3, 2014 SRT's before I bought mine. And everyone of them had a noticeable miss at high idle when we started them up. Not one was immune. Now my wife, who hasn't the first clue about cars can't tell its missing. But if you know what a miss feels like its as plain as the nose on your face. It sputters a little audibly and produces an ever so slight vibration during this high idle period. The moment the engine idles down it smooths right out and is obviously no longer missing. It doesn't miss while driving either. But here's what is happening in the computer. It registers those misses on a counter. If those misses rise to the level of a percentage of engine revolutions the CEL is turned on.

Now let's go back to what I was saying before about often times this CEL comes on shortly after a buyer takes delivery. Why? Well lets consider that when it rolls off the line there is a quick test of the car. So they start it up and it high idles while they test it. It registers misfires. That is stored in the computer. Then the car is started again and loaded on a truck. Then it is started again and off loaded at the dealer. Then it gets moved around the lot God knows how many times. Then people take short test drives. Then it gets moved some more. Then you buy it. Then they take it back to clean it and fill it with gas for delivery. All of those are cold starts. Meanwhile the high idle is missing and the computer keeps racking up the misses. So on the way home you don't put a lot of miles on it. Then the next day you drive it to work and the number of revolutions on the engine have been met to judge if there is an issue and the number of misses have racked up that the ratio is satisfied and BAM the light turns on. There are countless posts on the internet about the CEL coming on shortly after someone takes delivery.

Now if you are anything like me, your car doesn't get driven very often. I drive mine maybe once or twice a week and when I do its very short distances. So if I reset my CEL and proceed to behave the same way, in so much as drive it once or twice a week for short distances then the process starts all over again. The misses from high idle relative to engine revolutions eventually gets me right back to the point that the requirements are met in the computer to trip the light.

How do I know this? Well, I have done some experimenting to validate this. If I drive my car every day and put a fair amount of miles on it. Say 30-50 miles per day the light stays out. Why? Because all those engine revolutions from driving without a miss (remember high idle is only on cold start and not many engine revolution occur during this short period of time) that the counter is overrun with non-miss events and washes away the miss events from the counter OR sees an acceptable ratio of misses to non-misses and doesn't trip the light.

So for someone who drives their car a fair distance everyday or someone who takes it out rarely but when they do travels long distances then this is never an issue for that person. Its not that your car doesn't have the flaw, it does, its just that your driving habits are preventing it from being noticeable to you. In fact, if your light is on... just go on a long road trip. Do some warm starts here and there. In a day or so the light will turn out all by itself.

Is this whole issue BS? Yes, of course. Should we have to deal with it? No, of course not. But I can't count how many of these threads where people take their cars in and dealerships just start throwing parts at the problem. Then of course they reset the code and pray. Now if you put a fair amount of miles on your car then for all practical purposes it seems like what they did fixed it. If you behave like me then guess what... your dealership looks like a bunch of fools who can't fix the problem.

And some of these repair stories are comical... First they replace the coil packs and plugs and eventually end up replacing the head only to find out the CEL is back on.

I am hear to tell you, if you have a 2014 392 and you are getting this error there is nothing mechanically wrong with your car. Your car suffers from a software bug in the computer causing high idle misses and is subsequently telling you you have a mechanical problem. Coupled with your possible driving habits and you have this mystery. The dealerships and Dodge or SRT don't own these cars. They don't know what we the end user know. That is why I have embarked on this campaign to make them aware.

I have inquiry into am online dodge rep about this. If I don't get anything back from him/her in the next week or so I will make it my mission in life to harass SRT until they acknowledge this problem and fix it.
 

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2010 stone whiteRT classic

Yes I totally agree with what you just said untop of the short trips and cold starts building carbon!Dave
 

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Happened to me ... went back to the dealership 5 times (and yes, a miss is very noticeable to the savvy ;) ). Let's see ... they replaced coil packs, cold start solenoid (?), and finally the entire exhaust (per Chrysler). When they replaced the exhaust, they said the engine light had come back on and that they needed to get with Chrysler to figure out what to do next. It was Friday, and I told them I needed my car for the weekend and would bring it back on Monday for further diagnosis. They cleared the code again, which came back on during the drive home from the dealership.

Well, what I needed my car for was an autocross. I took her out and flogged the snot out of her. At some point during my 5 runs the CEL went out, and hasn't been back on since :4-dontknow:. Best I can figure is that something needed burning out.

Someone else posted a case number with Chrysler on this issue ... I'll see if I can find the thread.

Edit: Ah, well, the star case was from your thread :D
 

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Had something similar happen to me on my 2014 SXT. After about two weeks of ownership, approximately 200 miles on the odometer. I started the car and it was stuttering pretty bad and the CEL was flashing. Shut the car off immediately and then restarted it. Started up perfectly normal, no stuttering no CEL. Checked for codes, none. I since put another 200 miles on the car with no issues. I am hoping it was some computer glitch, or bad GAS. Who knows, if it happens again I will contact the dealer. Anyone ever experience this?
 

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Discussion Starter #6
Had something similar happen to me on my 2014 SXT. After about two weeks of ownership, approximately 200 miles on the odometer. I started the car and it was stuttering pretty bad and the CEL was flashing. Shut the car off immediately and then restarted it. Started up perfectly normal, no stuttering no CEL. Checked for codes, none. I since put another 200 miles on the car with no issues. I am hoping it was some computer glitch, or bad GAS. Who knows, if it happens again I will contact the dealer. Anyone ever experience this?
Sorry I don't think I can be much help with that issue. I just want to be clear that all P0300's are not necessarily created equal. I realize you didn't have an error. And at no point does the condition I mentioned earlier ever produce a flashing light. A flashing light indicates an active issue and is usually accompanied by a code. The CEL may not be on but I wouldn't be surprised if there was a stored code. You should probably take it to the dealer for investigation. At no point does what I described ever produce a bad vibration like what you are describing.
 

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Same problem with 2014 SRT with under 5k miles. Chrysler had the dealership replace the heads but two days later same misfire code appeared. Took it back because the check engine light came on durning start up. Was told the misfire code was activating durning start up. Called dealership again about, still waiting for answer. Thinking of having dealership buy it back for a new one but apprehensive of same problem.
 

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Well it's been about two months now an 1k miles since I had the issue.
The car has been running perfectly, no sign of anything. Idle is rock steady
and the motor is silky smooth right up to the redline. Hopefully it was just bad gas from sitting on the dealer lot. I am pretty sure it would have happened again if it were a real problem. I'll keep my fingers crossed, really like this engine.
 

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I think what these cars are saying to yall/us is "drive me please" "don't save me drive me and enjoy me to the fullest." I dont have an SRT but all cars the made to be driven and you should, no reason to make it a garage queen. I drive mines the minute it gets warm and all the snow is gone till the first sighing of snow on the forecast. Aye drive that car man!!!!!
 

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Great Thread

Thanks for the information. 1300 miles on month old SRT and same issues. Was taking to dealership but now I will just hot start it. Borrowed a diagnostic scan and codes 300 307 came up.
 

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Replacing Spark Plugs, Coil Packs, The PCM, and/or everything associated with the ignition system and the problem is not fixed. Then they replace a cylinder head? Really?
Why not replace the rear bumper?
Engineers have figured out easy ways of detecting misfire. One is back EMF from the coil, meaning that when there is high voltage discharge, the collapsing field of a coil that does not fire the plugs--such as in a fouled or direct short to ground condition has different electrical characteristics than that of a coil that has fired and discharged it's secondary voltage properly.
A great thing about these ignition systems on the HEMI is that it is nearly impossible for one of the plugs to not fire because the secondaries voltage path is through both plugs. One side of the coil does not share a ground to the engine block. The other plug IS the ground path. One plug has the spark jumping from side electrode to center and the other jumps from center to side.
The other way to detect misfire is that on a smooth running engine without misfire, a perfectly spaced pulse train of signals is generated by the sensor on the crankshaft and camshaft. If a misfire occurs, the spacing is greater between the first and third pulse meaning that the cylinder in-between did not fire. The engine has slowed down a significant amount in between the firing of the plugs. Since the PCM keeps track of which cylinder was supposed to fire, it now knows which one did not. Cool eh?
Where am I taking this note?

Well.... since there are a lot of bright guys out there (women too, but a Guy found this) that this problem was bugging, one of them was about to find a solution...

Remember all the silly things service departments have replaced and it did not fix the problem?

How many of you know what Water Hammer is? Have you ever seen a capped riser pipe beside a water heater to cause a gap of air in the system to prevent your plumbing from banging when someone shuts off a faucet too fast?

Well anyway, the problem is bubbles in the fuel rail. These engines cannot fire an ultra-lean condition. They seem to get trapped over on #7 for some reason.
On the test mule vehicle, 4 small pipes about 3" high were silver soldered into the ends of both fuel rails with those things that look like a schrader valve on the end. But is has to be the kind used on fuel systems like where you would measure fuel pressure. This gives the bubbles a place to go and the misfire problem goes away forever. When you first start the engine, you depress those mini plungers to purge the air in the riser pipes, and you are done. Don't ask me how I got this info. If you know what you are doing and are capable of the mod, just get it done and you will never see the problem again.

Well...wait a minute, you might need to pop those plungers once a year to purge the air out.

-John
 

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Well anyway, the problem is bubbles in the fuel rail. These engines cannot fire an ultra-lean condition. They seem to get trapped over on #7 for some reason.
On the test mule vehicle, 4 small pipes about 3" high were silver soldered into the ends of both fuel rails with those things that look like a schrader valve on the end. But is has to be the kind used on fuel systems like where you would measure fuel pressure. This gives the bubbles a place to go and the misfire problem goes away forever. When you first start the engine, you depress those mini plungers to purge the air in the riser pipes, and you are done. Don't ask me how I got this info. If you know what you are doing and are capable of the mod, just get it done and you will never see the problem again.

Well...wait a minute, you might need to pop those plungers once a year to purge the air out.

-John
Interesting... would that be a warranty approved fix?
 

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If not cleared up by the time I buy my SRT I will know what the deal is. Thanks for explaining the CEL cause. Does not sound like a dealer problem. Like Marc Phrey said: Just drive it. I do the same. In the garage for winter and rest of the year drive it every day and no problems. Great car.
 
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