1G MMCd fuel trim issues stuck @ lean?

[93AWDDSM]

I'm logging with MMCd and I reset the ECU to start fresh but no matter what my fuel trims go lean.. low is 137%/Med is 112%/High is 108%. The car is stock besides larger 16g (14-15lbs but going to turn it down to 12) turbo and a lower honeycomb removed from the stock MAS (The VC breather hose isn't hooked up to my intake pipe either FYI). Can I get some guidance on why it's so lean? This is just cruising also not WOT.

I was reviewing the logs and it seems like I get anywhere from 12-43 counts of knock in 1st/2nd slow acceleration as that's where its leanest and more so when it's colder.

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[93AWDDSM]

So a few things done but no change.
-replaced turbo inlet gasket, stopped leak there

-regapped spark plugs

-reran some “issue” vacuum line from IM to BOV

-checked o2 sensor (cycling as it should)

-BLT, didn’t find anything extreme and held decent pressure but I will do another test on Friday

Have not checked/replaced:
-fuel filter
-VC breather hose is just hanging into engine bay not recirculated. I do have a 3/8 check valve before the PCV into the Valve cover though.

I saw a few threads that this COULD be pulling in unmetered air at idle/low throttle causing issues?

 

[Vegas Smith]

I would reconnect all your vacuum lines to the correct location because the stock mas system is very finicky. Also, there is no reason you should be getting that amount of knock. Either the sensor is in the wrong location (double and triple check this) or the sensor is bad.

 

[93AWDDSM]

Yeah, I have a dejon hard Intake pipe that I will be installing a vacuum nipple for the VC breather line. I will definitely check my KS location today and am just going to swap with a different one.

The knock is ridiculous. It’s Mainly around 2.5-3.5 rpm but if I let off the gas, knock count drops to zero and I give it gas it drives normal with no knock .

 

[93AWDDSM]

So I was thinking my fto2 are definitely in the lean according to the logger.

Could the exhaust leaks be so bad at idle and cruise that it’s pulling in fresh air and changing the o2 trim value to lean but I’m getting enough air actually to the motor so it’s flooding it with fuel per the o2 trim cycling between 115-154% logging at cruising low rpms?

 

[BoostedTalonTS]

Once you eliminate all of the intake & exhaust side leaks (be sure to check the TB shaft seals) and you can rule out erroneous o2 sensor values being fed to the ECU, you can bump up the base fuel pressure easily by installing an NA or a turbo Auto FPR... Stock MT's FPR has a BFP of 37psi, vs the NA & AT Turbo's 43psi FPR... physically they're directly interchangeable! This will help offset the increased incoming (un-monitored) air from the lower honeycomb being removed from the 1g MAF & the higher flowing B16g

 

[93AWDDSM]

I’m getting a can of SEAfoam to run through. My knock counts are getting ridiculous. I’m hoping the SEAfoam will easily pinpoint which exhaust leaks I need to repair (gaskets). I just watched a video with a guy claiming to have 420k on his 90 talon and he was seafoaming the hell out of it. I’m only 200k behind him! Haha.

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This is at normal accelerating... I can’t really even drive it..

Here’s a vid at idle.
https://streamable.com/7cdz1

 

[93AWDDSM]

Lol ran the SEAfoam expecting tons and tons of crap come out, I had the head rebuilt and cleaned 2 years ago so not much there. Didn’t get really any dirty exhaust or any from the exhaust manifold, turbo or o2 area.

I did something that’s probably a big no no. I moved my knock sensor one hole down by the ac bracket. I then readjusted my base timing to around 5* and then went on a drive. The knock count was down significantly, I didn’t get into Boost but just cruising I got very little knock and throttle response felt good without any hesistion.

Am I in the wrong here?