Fuel Trim on Bank 2 - Causing misfires

[rj124104]

Car was running fine prior to work.
Replaced PCV, Valve Cover, Thermostat, Water Pump, Rebuilt Vacuum Pump, New upper and lower gaskets on intake manifold, new o-rings and gaskets for injectors. New coils and plugs.

Car misfires at idle and cannot be driven.
Bank 2 is having a 19% fuel trim at idle which is undoubtedly the issue. Looking for advice on what could be broken/wrong.

Things I've done to diagnose:
Replaced and vacuum tested solenoids on back of supercharger.
Confirmed flaps open and close under vacuum with hand pump.
Tested fuel pressure - seems normal, pressure spikes after vehicle is turned off indicating no leak.
Reseated intake manifold multiple times in case gaskets are leaking.
Replaced PCV breather hose.

Any suggestions on where to look for what's causing it? Specific Vacuum line, etc. I am assuming since it's isolated to one bank seemingly that there is a specific item causing it. Any advice would be helpful.

[Low Flyer]

Still chasing the same problem I've had for weeks, but today made a discovery with VCDS. Bank 2 is having a 19% fuel trim at idle. Any suggestions on where to look for what's causing it? Vacuum line, etc. I recently did PCV with all new gaskets. Checked fuel rail pressure when car is shut off and it climbs and seems to be holding so I don't believe there's a fuel leak. Any advice would be helpful.It may sound strange but, the dealer had mine for 69 days, for a similar issue. Ended up being my catalyst.

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[rj124104]

It was running fine prior to the PCV operation or I might consider something other than my own fault. Has to be something I did, I'm assuming vacuum line (although I thought I tested all of them) or something broke like the actual manifold. Just need to know what would do this to bank 2.

[rj124104]

Is it possible the intake manifold cracked? At what point is the system measuring the air entering the intake. Is it post manifold meaning it's reading air actually entering the cylinder?

[rj124104]

Updated post for more specific info

[rj124104]

Smoker comes tomorrow. I’m surprised no one has ideas. Maybe we’re not wrench turners.

[rj124104]

Smoke didn’t find anything although I’m not certain it could have. I replaced my vacuum pump in case the rebuild caused issues. Still no luck. Car smooths out around 2,500 RPM but above it sounds awful and below. Not sure if that helps diagnose.

[Johnson]

You check your plug gaps? Just spit balling ideas here. Did you log low and high pressure side for fuel pump? Did you check fuel pump activation % at idle? Mine runs around 27% at idle.

I don't know if it cold be injector seal related?

Any codes when scanning with VCDS?

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[rj124104]

Thanks man, any ideas are better than no response. Spark plugs I've been through 3 sets just messing around. They're good. I've replaced the injector o-rings and gaskets now, still crosses my mind as a possibility or even that maybe they're clogged. Again, the car ran fine prior to me doing PCV and Carbon clean.

This is what I was looking at https://www.youtube.com/watch?v=SP2Yp7ocuVo and this is just kind of random me trying to hear any leak or anything https://youtu.be/k5uU0Tc8La0 .

Here's a couple pictures of VCDS as well. Sorry for weird video/images not sure what conversion they did. https://imgur.com/a/Ls5Qexx

[rj124104]

I replaced my crankcase breather hose with a non oem one. The "fake" as we'll call it only uses a single o-ring to seal. I'm wondering if that could potentially cause the issue (granted I don't hear a leak). I ordered a new one. Everyone has advised me that stalling and being unable to drive would be a bigger vacuum leak than just a small line. Anyone agree / disagree with that?

[killer_s4]

I’m not sure on this platform but for an engine to stall it has to be a pretty decent vac leak. I would redo your injectors and double check that work. Can you swap bank 1 and bank 2 injectors and see if the problem jumps?

[rj124104]

I have it torn apart right now so I'll swap them around. I soaked them when they were out, but now I have a injector tester that will make them pulse to clean / test. I also plan on testing resistance. Anyone know the OHM measurement for our injectors on the 3.0T?

[JD S4]

You could have one of the vacuum lines on the back of the SC swapped around. I’d make sure your vacuum routing is spot on.


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[rj124104]

I've verified vacuum hoses are correct, thank you for the suggestion though.