Help with diagnosing lean bank 2

JC SSP

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I don't think its fuel since he's within the 35-45psi range... unless the pump is cutting on/off?
 

Kyleag89

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I replaced the pump 2 days ago and so far my trims have come down. Not to where I think they should be but they've definitely come down. Isn't it something that the long-term fuel trim will take a little bit of driving to come back down to normal? I've also been playing around with forscan and haven't found anything wrong or out of ordinary. Fuel trims at idle are <5% and behave better under load.
 
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Kyleag89

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Just wanted to update this thread in case anyone finds it useful in the future. The car is running great and no more lean codes have popped up! My LT and ST fuel trims both are at +1 according to the sct tuner. I picked up a used unmarried tuner for $140 locally and tuned the car for the BBK intake but the fuel pump and intake manifold leaks(tiny) is what fixed my issue. I am assuming although I had great fuel pressure according to my OBD2 scanner the original pump with 93k miles on it wasn't delivering enough volume. The pump sock and filter both had a lot of dirt clogged in them however the tank was spotless inside.
 

86GT351

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That honestly doesn't matter. A Lean condition is unmetered air, which means are PAST the MAF sensor. I don't care how much air you give it before the sensor (hood scoop, ram air, NO hood, doesn't matter). You need to verify you have the correct fuel map corresponding to the CFM and diameter of the opening the MAF lives in. I still think you need a reflashed tune to the BBK
This! It takes 3 things to run the engine. Air, Fuel and Spark. By modifying one of th e3, you could easily be changing the way the vehicle runs. Too much air can change things very quickly.
 

SteezStang

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I’m a little late to the party, I had a bank lean condition and I found residue underneath one of my runners, found out I had a failing gasket on my manifold, cleared the code after replacement and it never returned
EDIT: glad you got her figured out
 

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