I Have a 2011 6spd r/t and i have P codes 0300, 0303, 0301. been in twice checked all my spark plugs swapped coils around and drove it 3 miles and could not replicate. happended to me at 3k and at 6k miles also i got the loud decel howl in any gear.....
any suggestions... my dealer wont help they say the car needs a break in period.....
i say BULL SHOOT
Loud decel could mean youre running rich assuming loud = backfire. I have not had codes, but, it could mean a number of things.
I seriously doubt the timing chain was the culprit as you can almost always hear something going wrong beforehand ... not something that sounds like combustion problems but something that sounds like pinging or rattling. A lot of 4 cylinder DOHC cars have problems like that. Plus you would have rough idling problems, loss of power, poor fuel economy and a bunch of other stuff. Same with the heads.
What probably happened was that it was something else and it eventually caused the timing chain and heads to die. Think about the fact that the initial symptom was misfiring... what happens if you don't fix a misfiring motor? In my experience you end up with jacked up internals and usually they did not cause the misfire to begin with. The timing chain would be especially vulnerable since it would bear some of the load caused by combustion occurring at the wrong times in the form of improper resistive forces in the motor (since you have the combustion fighting the piston instead of helping it move ... and the valves as well since they wouldnt be seated at the correct time).
Plus the same timing chain has been used (presumably) since the gen 3 hemi came out and I have not seen this issue come up on other car or truck forums. I would look elsewhere for the problem first. Poor gas, bad ignition system, bad programming, bad mixture, bad head gasket, detonation for whatever reason, VVT stuck in the wrong mode, MDS failure on non-6spds (doubtful but maybe), a bad electrical ground or contact (which OBDs are awful at diagnosing), something else ... something to cause the misfire that led to the bad chain and heads. Just because they happen to fix it by nearly overhauling the guy's motor doesnt mean that what they repaired was the origin of the issue because ultimately they had to rework and replace many other things in the process.
That's my $0.02 anyways...
take it or leave it.