Hey I’m Johnny, so recently well back in Oct 2025 I went back to stock for getting reffed. After going back to stock I later found out I had a cracked passenger exhaust manifold. When swapping everything went smooth but I got hit with a P2A00 code. Where the war began.

So at the time I ended up swapping the Bank 1 sensor 1 AFR sensor. Didn’t fix the issue of-course. After reading around and coming across multiple opinions. I started to diag and play around with different sensors. I swapped the bank 1 cat for a friends one and it didn’t fix the issue. After that I decided to swap my bank 2 cats as well because it was bad. While swapping the driver cat I decided to swap out the AFR sensor for bank 2. When doing that, the code came back to Bank 2 this time! (P2A03). Any ways I’m able to see live data with my ecutek app. Whatever bank is leaning out. The voltage always is at 1.5-1.9v for AFR and for heater o2 sensor for the cats are at 0.09v, keep in mind it does react when driving or reving the car. But just goes back down. anyways after seeing it swap to bank 2 I decided to put the old AFR sensor back into Bank 2 the lean code went back to bank 1. (Weird right?) So I ended up buying one new denso AFR sensor to test if it really was just the sensor itself. Ding ding it was not at all.

Now that I swapped both cats. And played around with sensors as well buying 1 new O2 sensor for the cats to see if that’s the issue. I Decided to smoke the system. I ended up seeing that I did have a hair line crack on my friends cat and another crack on Bank 2 exhaust manifold. So that being said. I ended up swapping both exhaust manifolds because I ended up going with 2014+ and my car is a 08. New gaskets for the manifolds and cats and as well I welded the hairline crack up. (Maybe I wasn’t supposed to do that but it’s a small crack by the support for the cat.) Now after doing the big job of swapping the manifolds and new gaskets.

Also forgot to include Before doing finding out that driver manifold was cracked. I had a hole on the resonator of the intake tubing for bank 2. And bank 1 tubing had a small crack on the clamp area that some what surpass the clamp. I ended up replacing those two with newish ones with no leaks. I smoked the Intake system and did not see any leak.

Now after doing the manifolds, and intake tubing. I still had the leak. Which leaves Injectors, fuel pressure, and checking mafs. Took off injectors to get cleaned and tested. Injectors came back perfect and cleaned. Put back in, still having leaning issues and code coming back. Checked fuel pressure and it’s within spec 50 psi. Now I was really lost, I decided to check maybe it was my ecu. I put another ecu and tested it. It was not that at all.

So this is where I need help. I don’t know what else to test. Only thing I can think of right now is re smoking the exhaust system again to see if something is still leaking. I have tested for shorts for Bank 1 sensor 1 and everything was a okay, I check if the ground was grounded and it was. I haven’t done it for bank 2. But I’m really in a loop right now. (As well while doing each swaps I was doing ecu resets and idle relearns) I’ve tried a different pair of mafs and that wasn’t the issue either.

now the issue just jumps between banks as well, for my Short fuel trims What ever bank it’s at, it’s at 115%- 125% which I know it’s really lean. So please if you guys have any other ideas I can try just let me know. Since I’ve gone through almost everything, I’m going to start from the basics and re diag everything again.