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P219b code and rough idle after replacing cracked header Help?

skid_valve

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Recently bought a 2021 ram 1500big horn 5.7 hemi with e-torque, I noticed it had a slight vibration at idle but it also had a cracked passanger manifold.

The other day I finally replaced the cracked passenger side header with the bd diesel replacement one, and immediately noticed the idle vibration got worse along with now getting a p219B check engine light code (bank 2 air fuel ratio imbalance) that comes back event after clearing.

What could this be? I’m worried about it being a valve train issue or maybe 02 sensor, idk how to reset the fuel trims but I do have alpha obd if it’s possible to do it with that. It is about to get an oil change as well if that’s important for context, any help is appreciated especially if it might be an issue with these engines I don’t know about especially seeing my truck is higher mileage at 167,000mi.

Thanks
-Skid_valve
 

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Recently bought a 2021 ram 1500big horn 5.7 hemi with e-torque, I noticed it had a slight vibration at idle but it also had a cracked passanger manifold.

The other day I finally replaced the cracked passenger side header with the bd diesel replacement one, and immediately noticed the idle vibration got worse along with now getting a p219B check engine light code (bank 2 air fuel ratio imbalance) that comes back event after clearing.

What could this be? I’m worried about it being a valve train issue or maybe 02 sensor, idk how to reset the fuel trims but I do have alpha obd if it’s possible to do it with that. It is about to get an oil change as well if that’s important for context, any help is appreciated especially if it might be an issue with these engines I don’t know about especially seeing my truck is higher mileage at 167,000mi.

Thanks
-Skid_valve

I don't see how the header could be causing this? (Pardon for the font size...)​

Possible Causes

INTAKE MANIFOLD LEAK AT A SPECIFIC CYLINDER ON BANK

EXHAUST MANIFOLD TO CYLINDER HEAD LEAK AT A SPECIFIC CYLINDER ON BANK 2

FUEL INJECTOR ISSUES AT A SPECIFIC CYLINDER ON BANK 2

IGNITION SYSTEM ISSUES AT A SPECIFIC CYLINDER ON BANK 2

CYLINDER COMPRESSION IMBALANCE

CARBON BUILD UP

VARIABLE VALVE TIMING ISSUES

VALVE TRAIN ISSUES

O2 SENSOR.
 
Last edited:

I don't see how the header could be causing this? (Pardon for the font size...)​

Possible Causes

INTAKE MANIFOLD LEAK AT A SPECIFIC CYLINDER ON BANK

EXHAUST MANIFOLD TO CYLINDER HEAD LEAK AT A SPECIFIC CYLINDER ON BANK 2

FUEL INJECTOR ISSUES AT A SPECIFIC CYLINDER ON BANK 2

IGNITION SYSTEM ISSUES AT A SPECIFIC CYLINDER ON BANK 2

CYLINDER COMPRESSION IMBALANCE

CARBON BUILD UP

VARIABLE VALVE TIMING ISSUES

VALVE TRAIN ISSUES

O2 SENSOR.
I mean I don’t either, but by fixing the manifold it got rid of the massive leak it had 🤷‍♂️ I just got my missing hardware to install the driver side header maybe it’s a slight difference side to side causing it. If it were valve train what would it be?
 
Good question

To add to it.. I also got that code after I fixed the manifold issues it’ll turn on for a few hundred miles then go off then reappear again eventually. Haven’t had time to really dig into it and figure out what could be causing it.


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Good question

To add to it.. I also got that code after I fixed the manifold issues it’ll turn on for a few hundred miles then go off then reappear again eventually. Haven’t had time to really dig into it and figure out what could be causing it.


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Did you replace both or just one ? Also did your idle get rougher?
 
Both but a day after each other and didn’t drive it far enough to notice anything. I haven’t noticed anything different with the idle but ill keep a closer eye on it next time it pops up.


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Both but a day after each other and didn’t drive it far enough to notice anything. I haven’t noticed anything different with the idle but ill keep a closer eye on it next time it pops up.


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Thanks for the info if I figure it out I’ll share it here and if you figure it out please do
 
I've worked through both of these issues on my truck as well and they were independepant issues.

My first question is, does your truck ever idle perfect, even just briefly? I ask because mine would, sometimes for a tank or two, sometimes only a partial tank but it was capable of idling smooth at times. This ruled out any worn cam, valvetrain or other permanent severe mechanical issue that RAMs can encounter. So I was able to narrow mine down to fueling/combustion issues. I switched to better fuel, higher octane and did a full tune-up at 100k miles but the ultimate solution for me was to run a couple bottles of the Chevron fuel system cleaner through it. I figured I had gummed up injectors but I also know I took on a bunch of water at a remote fuel station out in the country one day. I was about to drop the tank and do a thorough cleaing but the Fuel System Cleaner did the trick and it hasn't come back. Currently at 138k miles and it idles so smooth you have to check to see if its running at times.
 
I thought mine could be gummed up injector related when it originally happened shortly after manifold replacement my tank had been sitting low for a while. I ran the code P219a and misfire I think on bank 1. No noticeable driving difference other than the CEL turned on. I tighten the two bolts on manifold to CAT some more did the soapy water test and ran the truck no noticeable leak so I caulked it up as a fault code especially since it occurred shortly after the manifold replacement. I refueled and short drives during the week it eventually went back out. It eventually popped up again several hundred miles later but I wanna say the misfire was a different cylinder this time.. same thing drove it around enough during the week eventually went back out. Drove it a few weeks ago from FL to VA it probably popped back on within a hundred miles or so left.. been staying here driving around tike here and there and its back off. Im positive its not valve train related so ill probably just start running a few tank with injector cleaner and monitor it from there.


Sent from my iPhone using Tapatalk
 
I've worked through both of these issues on my truck as well and they were independepant issues.

My first question is, does your truck ever idle perfect, even just briefly? I ask because mine would, sometimes for a tank or two, sometimes only a partial tank but it was capable of idling smooth at times. This ruled out any worn cam, valvetrain or other permanent severe mechanical issue that RAMs can encounter. So I was able to narrow mine down to fueling/combustion issues. I switched to better fuel, higher octane and did a full tune-up at 100k miles but the ultimate solution for me was to run a couple bottles of the Chevron fuel system cleaner through it. I figured I had gummed up injectors but I also know I took on a bunch of water at a remote fuel station out in the country one day. I was about to drop the tank and do a thorough cleaing but the Fuel System Cleaner did the trick and it hasn't come back. Currently at 138k miles and it idles so smooth you have to check to see if its running at times.
I thought mine could be gummed up injector related when it originally happened shortly after manifold replacement my tank had been sitting low for a while. I ran the code P219a and misfire I think on bank 1. No noticeable driving difference other than the CEL turned on. I tighten the two bolts on manifold to CAT some more did the soapy water test and ran the truck no noticeable leak so I caulked it up as a fault code especially since it occurred shortly after the manifold replacement. I refueled and short drives during the week it eventually went back out. It eventually popped up again several hundred miles later but I wanna say the misfire was a different cylinder this time.. same thing drove it around enough during the week eventually went back out. Drove it a few weeks ago from FL to VA it probably popped back on within a hundred miles or so left.. been staying here driving around tike here and there and its back off. Im positive its not valve train related so ill probably just start running a few tank with injector cleaner and monitor it from there.


Sent from my iPhone using Tapatalk
Putting some injector cleaner through it probably isn’t a half bad idea. I’ll change out the other header and put some in to see if it goes away, if that doesn’t work I’ll pull the injectors and put them on my flow bench
 

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