219B Engine Code?
 

Hey there 👋, newbie here. I have a 2013 Silverado with the 5.3 in it. I recently have had a 219B code pop up, Fuel/ Air Imbalance)..
I’ve changed both the upper and lower O2 sensors cleared it and it has now came back. I have looked for visible signs of blackening from exhaust leaks around the manifold and stuff but have found nothing. I’ve stethoscoped all of the injectors on the passenger side (bank 2) and heard very loud visible clicking. I’m lost on what to do next, as I have taken it to the dealer after doing the items above and they couldn’t find anything..

1) The injectors all having the same audible click does not mean one or more of them isn't leaking. Perform fuel pressure testing on the engine when it's cold and warm (at operating temp). Once the gauge is installed, run the engine about 30 seconds to purge any air from the gauge and fuel rail, then shut the key off and return to the ON position (but do NOT start it). Watch the gauge - an initial drop of 1-2 PSI (depends on the gauge) is normal - but within 5 seconds of key ON, the reading should stabilize and not lose more than 2 PSI in 5 minutes.

If it drops 2 or more PSI in 5 minutes, you can rule out the fuel pump check valve (and FPR, if equipped) by pinching off the flexible section of fuel hose after the system is primed. If it still loses 2 or more PSI with the lines pinched off, leaking injectors are the culprit. Best to use hose-pinching pliers with a rounded edge. If using vice grips, either put a couple layers of duct tape on the jaws or wrap the line in a rag. The goal is to cause a blockage that holds fuel pressure - vice grips can easily cause kinks or tear/cut the lines if they're not padded.

2) Exhaust leaks can also be located by "plugging" the tail pipe, then using regulated compressed air into the exhaust at 10-15 PSI. Use a spray bottle of soapy water at the manifolds & converters to check for leaks just as you would a tire. What I find is easiest is to insert the air hose into the tail pipe and then use a rag or 2 to stuff into the tail pipe and help seal it. You won't get a 100% seal but it should be good enough to hold for the check. Consider also using duct tape to seal the pipe with the hose running through it.

3) I don't know if the P219B was included, but GM did issue a TSB regarding misfire and/or oxygen sensor codes. They determined the cause could be due to ignition coil grounds that are corroded or broken at the ring terminal. Removal for inspection and repair was necessary. The grounds for your engine should be at the left front of the cylinder head for bank 1 and the right rear of the cylinder head (or the top right rear of the block near the oil pressure sensor). My advice is to just replace the eyelets - it's only a few minutes of work and worth it to know they're good.

4) SOME trucks of this era were sensitive to the brand of O2 sensor that's used. I'm not one to say that OEM parts are the only way to go, but if you opted for aftermarket sensors and are unable to find any other causes, you might want to consider replacing them with OEM sensors.

What ended up being the issue? I’m dealing with the same code after the dealership replaced my engine 6.2.

No idea yet, I've paid probably close to $2000 and it just came back on after about four months. the last dealership I took it to flashed the ECM and it went away but I will say when I got it home it still had the same sensors showing invalid/ not ready. Unfortunately, I think they have done something shady to get it to pass emissions. Now once again I have emissions coming up in July and have the same problem again....

I have noticed it bogs down slightly at startup and has a little bit of rough idle initially. This settles out as soon as it warms up.
Sorry to not be of nay help, let me know if you find it before me and I'll do the same