Codes P0456, P0304, P0420 and P0306?

Tiny
OLIVERERIC423
  • MEMBER
  • 2013 DODGE GRAND CARAVAN
  • 6 CYL
  • 2WD
  • AUTOMATIC
  • 155,000 MILES
I’ve had this vehicle for almost 3 months and ever since getting it, it’s been nothing but a headache. When we got it, at red lights or stop signs it would stumble slightly then correct itself until accelerating where it would again stumble slightly then be fine. We ended up getting a p0456 code and were told the most likely cause was a faulty purge valve, we replaced it, had the light reset and along we went. We hoped it would fix the problem but didn’t, still sputtering before finally the car would shut off after the sputter during idle. We then got the code p0420. The dealership was busy for a few days, so we waited and eventually the code turned off. When we went to the dealer they said because it was not an active code, they couldn’t do anything about it, so we just got the o2 sensors changed hoping maybe that would help. After that, the sputter stayed, and we eventually got codes p219b and p0302. While waiting for pay day to get the spark plugs, coils and boots changed, we also received codes p0304 and p0306. Any idea what can cause this? We love the van and just want to be able to fix it so we can drive it without worrying we may be stranded on the side of the road somewhere.
Tuesday, September 6th, 2022 AT 3:27 PM

1 Reply

Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 110,055 POSTS
Hi,

There are a lot of codes, but I feel they are all related to one issue, the P219B

P456 Small Evap Leak. I'm not sure why they suggested a purge valve, but that doesn't make sense for this code. Because it is a small leak, it could be anything. What needed to be done was to smoke the EVAP system to determine where the leak was located.

The P420 indicates a faulty catalytic, which is likely the result of the P219B. Additionally, the P302, P304, P306 are all misfires on bank two. The code, P219B indicates an air/fuel ratio issue on bank two. So, the misfire codes and catalytic converter code in my opinion are due to the P219B. Note: A purge valve would not affect only one side of the engine.

P219B indicates an imbalance of fuel on bank two. In other words, one side of the engine is either getting too much fuel or too much oxygen. This can happen as a result of several things. For example, an exhaust manifold leak at the engine, an intake manifold leak on a specific cylinder, fuel injector issues, variable camshaft lift failure, an ignition problem, and so on.

Okay, before I make your head hurt (because mine is) LOL I need you to simply listen for an exhaust leak near the engine. Open the hood and listen for exhaust or even a tapping or ticking sound.

If there are no leaks, I need you to check for engine vacuum leaks.

Here is a link that explains how that is done:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

If nothing is found and rather than giving you a hundred things to check, I would like to know the short-term fuel trims when the engine is running at operating temp. This requires a scan tool that has live data. This will tell me if the issue is related to high fuel pressure, a leaking injector, or an engine vacuum issue. I don't know if that is something you can do or have done, so let me know.

Let me know if this helps, if you have questions, or if there is anything I can do to help. Also, let me know the results of the things checked.

Take care,

Joe

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Tuesday, September 6th, 2022 AT 7:41 PM

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