Howdy. I've searched high and low and haven't found any threads where the P219B (Bank 2 air/fuel imbalance) code issue has actually been solved on a 2013 6.2 Raptor so figured I would post my issues here. From what I've read, this code can be a result of many things, including clogged or damaged cats (from too much dumped unburned fuel), bad O2 sensors, leaking or failing injectors/gaskets/o-rings, bad control purge valve, bad PCV valve, bad MAF sensor, air leak, exhaust leaks, etc. In most of the forum posts I've seen where people were attempting to solve this issue, the P219B code was accompanied by other codes which could be used to help solve the issue. In my case, Forscan is ONLY pulling the P219B code, even after resetting CEL and driving hundreds of miles.

My spark plugs and O2 sensors have all been replaced within the last 25k Miles (plugs due to age, O2 sensors due to failing one by one) (truck has 130k miles). I also recently installed a Fuse 27 (fuel pump) relocation kit, new fuel pump, and new fuel pump module after I had a no start/fuel starved condition last November. I just last week replaced the Control Purge Valve based on another forum post but that did not solve the issue and I'd hate to keep throwing parts at it without knowing more about what my symptoms mean. Well, okay..I did order a new PCV valve for $7 which I'll be installing tomorrow, but I know it's wishful thinking to hope that's all it'll take so I want to prepare myself for the next steps. Here are my symptoms:

When I go to start the truck, half the time it fires right up, half the time it sputters dead as soon as I let off the key as though there is no fuel. All I have to do is flick the key once more and it'll start and run without dying. Once it's running, it will idle fine one minute, then idle like **** the next. Sometimes rough like it's low on fuel, sometimes high like too much fuel. When it's under load, no problems at all. The throttle is responsive and she'll get up and go without hesitation.

Any leads on what I should try next would be much appreciated. Hoping it's not injectors or cat.

 

Being only on bank 2 that at least isolates it. If its not a bad signal from the o2 sensor then its more than likely unmetered air. Id start by monitoring the fuel trim when its acting up and make sure the o2 sensor is actually working properly and relaying the appropriate signal. If that checks out id move on to finding a potential air leak. Spray around your injectors with starter fluid and see if the idle speeds up, same for manifold gasket.

My bet is an air leak as any actual part failures would be accompanied by specific codes as well as the general code you have.