P304 on tunes 2015 with 21kmi

[BEAST19]

Ok fellas ... I have a 2015 5.7 with long tubes, jgreen tune and pedal commander . Upon startup after truck sits for a day or more I get a start that almost seems like the engine I totally doesn’t have enough fuel for start up... idles a tad rough and equalizes after about 3 secs .... every now and then it’ll throw a p304 code cylinder 4 misfire....
I clear code and after about ten more starts like described it comes back on.


Wondering if it’s due to the tune and or the pedal commander .... other than that truck runs flawless . Any ideas??


Sent from my iPhone using Tapatalk

 

[crackerjack1957]

You need to speak with jay.........

Could be PC, disconnect to see if it reoccurs.
Also could try swapping coils to see if it changes to another cylinder.


Common Problems That Trigger the P0304

• Worn out spark plugs, ignition wires, coil(s), distributor cap and rotor (when applicable)
• Incorrect ignition timing
• Vacuum leak(s)
• Low or weak fuel pressure
• Improperly functioning EGR system
• Defective Mass Air Flow Sensor
• Defective Crankshaft and/or Camshaft Sensor
• Defective Throttle Position Sensor
• Mechanical engine problems (i.e.—low compression, leaking head gasket(s), or valve problems

 

[cuminslvr]

I had a similar problem with the wife's car. Turned out rodents had eaten thru the ignition wire for 1 cylinder. Although it ran rough period. Never smoothed out. Simple thing to check, just run the wires to make sure there aren't any breaks or Bite marks lol..

 

[Reaper]

Following. I’ve got a 2013 with the same errorcod P0304 (cyl 4 misfire). Only 30,000 miles, I was 2k shy of spark plug change and I went ahead and did those. I thought that fixed it, but here I am ~500 miles later with the same error. I read on here to swap the coil pack to a different location, and if the error code follows it, then its a bad coil pack. I did the swap today, now to put some miles on it and see if the error follows.

 

[Reaper]

Well CEL finally popped up again today and got the same “P0304” code for cyl 4 misfire.

So I guess that means its not the coil pack like I hoped.

Can anyone suggest the next cheapest thing to check/replace?

This is really weird it just rough idles on startup for <20 seconds, then seems to run fine.

 

[Wild one]

Well CEL finally popped up again today and got the same “P0304” code for cyl 4 misfire.

So I guess that means its not the coil pack like I hoped.

Can anyone suggest the next cheapest thing to check/replace?

This is really weird it just rough idles on startup for <20 seconds, then seems to run fine.

Camshaft and lifters.

 

[StoneDude76]

Well CEL finally popped up again today and got the same “P0304” code for cyl 4 misfire.

So I guess that means its not the coil pack like I hoped.

Can anyone suggest the next cheapest thing to check/replace?

This is really weird it just rough idles on startup for <20 seconds, then seems to run fine.

My truck has been doing the same at start up. Rough idle with a heavy tick and what I assume is a misfire. It smooths out after about 10 seconds. I'm thinking one of the lifters is not pumping up fast enough. The thing is it got worse with PUP 0W40 and the SRT Filter. I switched back to PP 5W20 and I now it's been happening occasionally. I know I'll be swapping cam and lifters soon. By the way no CEL.

Sent from my VS988 using Tapatalk

 

[Reaper]

My truck has been doing the same at start up. Rough idle with a heavy tick and what I assume is a misfire. It smooths out after about 10 seconds. I'm thinking one of the lifters is not pumping up fast enough. The thing is it got worse with PUP 0W40 and the SRT Filter. I switched back to PP 5W20 and I now it's been happening occasionally. I know I'll be swapping cam and lifters soon. By the way no CEL.

Sent from my VS988 using Tapatalk

I’ve run Redline 5w20 and a Royal Purple filter since 5k. This is a cream puff of a truck (my wife’s words). 2013 with under 31k miles.

I’m literally 10 days past the 5yr powertrain warranty today. Any chance Ram would cover this? (If anyone has hookups at Ram/Ram cares...please let me know).

Thanks.

 

[BEAST19]

My truck has been doing the same at start up. Rough idle with a heavy tick and what I assume is a misfire. It smooths out after about 10 seconds. I'm thinking one of the lifters is not pumping up fast enough. The thing is it got worse with PUP 0W40 and the SRT Filter. I switched back to PP 5W20 and I now it's been happening occasionally. I know I'll be swapping cam and lifters soon. By the way no CEL.

Sent from my VS988 using Tapatalk

Can you upload a video.? I have no tick or atleast I don’t seem to hear one. Hears mine ... same?



Sent from my iPhone using Tapatalk

 

[Hemi450hp]

Misfire codes can be caused by numerous things. First step is to pull that #4 coil pack off and check the plugs. If the plugs look good, then swap the coil to another cylinder and see if the error code follows it to the next cylinder. If it still throws #4, then it would be a bad injector on #4...again, swap it to another cylinder and see if the problem follows.

If it still shows on #4 after trying these things, then its possible that you have a lifter on the way out that is not eating away at the cam. I just had to replace my cam and lifters on my 2015 with 51,000 miles on it. The failed lifter issue is more common than I like to admit on these trucks, but that is the last resort in diagnosing a misfire code.

 

[Tach_tech]

Swap components with known good cylinders, spark plugs,coil, and injector. If it’s still on the same cylinder it’s either mechanical or an electrical issue, but most likely mechanical.

 

[Reaper]

Misfire codes can be caused by numerous things. First step is to pull that #4 coil pack off and check the plugs. If the plugs look good, then swap the coil to another cylinder and see if the error code follows it to the next cylinder. If it still throws #4, then it would be a bad injector on #4...again, swap it to another cylinder and see if the problem follows.

If it still shows on #4 after trying these things, then its possible that you have a lifter on the way out that is not eating away at the cam. I just had to replace my cam and lifters on my 2015 with 51,000 miles on it. The failed lifter issue is more common than I like to admit on these trucks, but that is the last resort in diagnosing a misfire code.

Ok, so I put in new plugs and swapped the coil pack with one that wasn’t throwing a code, neither worked. Several have said the next thing to check is injectors by swapping with one from another location. But I can’t find a vid for our 4th gen hemi’s. Anything special I have to do (depressurize fuel sys)? Or are they simply unscrew and swap?

 

[Tach_tech]

They’re pretty simple to swap. You can pull the fuel pump fuse and let it run till it dies and that’ll get rid of a good portion of the fuel in the rail.

It’s a good idea to use compressed and and blow all the dirt/dust away from the rail so you don’t get dirt it anywhere it shouldn’t be.

Disconnect the injectors. Remove the bolts for the rail, remove the clips holding the injector in, then just pull out the injector.

 

[Reaper]

I knew there had to be a trick so I didn’t end up with a gallon of gas on me.
Thanks for the info, I’ll give it a shot this weekend.

 

[BEAST19]

You need to speak with jay.........

Could be PC, disconnect to see if it reoccurs.
Also could try swapping coils to see if it changes to another cylinder.


Common Problems That Trigger the P0304

• Worn out spark plugs, ignition wires, coil(s), distributor cap and rotor (when applicable)
• Incorrect ignition timing
• Vacuum leak(s)
• Low or weak fuel pressure
• Improperly functioning EGR system
• Defective Mass Air Flow Sensor
• Defective Crankshaft and/or Camshaft Sensor
• Defective Throttle Position Sensor
• Mechanical engine problems (i.e.—low compression, leaking head gasket(s), or valve problems

Disconnected pedal commander... no change .. rough idle for about 5 seconds as seen in video posted below in thread.... then runs normal. Doesn’t throw code every start either ......

And only has “ hesitant start” and short running rough idle upon initial start... if started shortly after ran or if it was ran that same day it starts up normally ... almost as if sitting causes the fuel system
To lose its prime if that makes any sense.


Sent from my iPhone using Tapatalk

 

[crackerjack1957]

Disconnected pedal commander... no change .. rough idle for about 5 seconds as seen in video posted below in thread.... then runs normal. Doesn’t throw code every start either ......

And only has “ hesitant start” and short running rough idle upon initial start... if started shortly after ran or if it was ran that same day it starts up normally ... almost as if sitting causes the fuel system
To lose its prime if that makes any sense.


Sent from my iPhone using Tapatalk

If you have done all the swaps on #4 as suggested by Matt.....I would say #4 lifter is not pumping up quick enough.
Try a Royal Purple filter if you are not currently using to help with bleed off.
Ask Jay is opinion also......I'm afraid you will have to replace cam & lifters.

 

[BEAST19]

If you have done all the swaps on #4 as suggested by Matt.....I would say #4 lifter is not pumping up quick enough.
Try a Royal Purple filter if you are not currently using to help with bleed off.
Ask Jay is opinion also......I'm afraid you will have to replace cam & lifters.

Ugh I’m afraid of that. Going to be doing a oil analysis soon. I am due for an oil change... I’ve been running a rp filter and redline 5w30 for prob 7k miles.


Sent from my iPhone using Tapatalk

 

[BEAST19]

If you have done all the swaps on #4 as suggested by Matt.....I would say #4 lifter is not pumping up quick enough.
Try a Royal Purple filter if you are not currently using to help with bleed off.
Ask Jay is opinion also......I'm afraid you will have to replace cam & lifters.

And if that’s the case I may be in the trade in market for a new 5th gen


Sent from my iPhone using Tapatalk

 

[Tach_tech]

Ugh I’m afraid of that. Going to be doing a oil analysis soon. I am due for an oil change... I’ve been running a rp filter and redline 5w30 for prob 7k miles.


Sent from my iPhone using Tapatalk

It’s possible that’s the issue but you’re at pretty low mileage for that to happen. Could have a broken valve spring as well. No other codes? Just the P0304?

 

[BEAST19]

It’s possible that’s the issue but you’re at pretty low mileage for that to happen. Could have a broken valve spring as well. No other codes? Just the P0304?

Yea just an occasional p0304 and a single p0300 (random cylinder misfire ) happened once.

I know I have a stripped throttle body bolt .... seems tight enough tho. Maybe bad gas? All this has happened recently within the past two months. (Keep in mind I rarely drive my truck )


Sent from my iPhone using Tapatalk