Intermittent lean while driving

[BlobbenEyeJoe2Slo]

Alright I need some help from the scoobie gods here.

Ej205 full bolt ons, id1050x and vf39

While driving, the car will randomly drop power for a second or less and pick back up in a bucking manner. Tuner is sure that it isn't the tune and it's something mechanical or electrical causing it. Afr spikes from 14.5ish to 19 to 22 for a few moments then it settles back down but it does this for several minutes. It also seems to do it during lower load more often then when I'm mashing on the throttle. Some days the issues is worse than others as well so it's incredibly intermittent but does feel like it's getting worse.

What I've tried so far:
Additional fuel pressure damper
New fuel hoses
New fuel filter
Vacuum leak test
New oem fuel pump relay
New oem main relay
New hella cam sensor
New diamond crank sensor
New denso o2
New denso maf
Pushed coil plugs to make sure they are seated
Additional ground from engine block to manifold and manifold to battery

What I've discovered about the car:
Previous owner spliced a new maf harness
Alternator harness has also been spliced

What i haven't replaced:
Throttle position sensor
IAC valve
Injector harnesses

mod list:
Jdm ej205
tgv delete
Aem 340 fuel pump
Bosch alternator 130amp
Cobb sf intake
Perrin turbo inlet
Nvidia turbo back
Tomei headers and uppipe
Vf39
Sti tmic
Phenolic manifold spacers

I replaced the plugs and coils with NGK 1 step colder and diamond coils less than 5000 miles ago as well while trying to figure out this issue.

I also have a log of just the bucking but I'm not sure how to post it here.

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[SusanJackson]

Originally Posted by BlobbenEyeJoe2Slo

Alright I need some help from the scoobie gods here.

Ej205 full bolt ons, id1050x and vf39

While driving, the car will randomly drop power for a second or less and pick back up in a bucking manner. Tuner is sure that it isn't the tune and it's something mechanical or electrical causing it. Afr spikes from 14.5ish to 19 to 22 for a few moments then it settles back down but it does this for several minutes. It also seems to do it during lower load more often then when I'm mashing on the throttle. Some days the issues is worse than others as well so it's incredibly intermittent but does feel like it's getting worse.

What I've tried so far:
Additional fuel pressure damper
New fuel hoses
New fuel filter
Vacuum leak test
New oem fuel pump relay
New oem main relay
New hella cam sensor
New diamond crank sensor
New denso o2
New denso maf
Pushed coil plugs to make sure they are seated
Additional ground from engine block to manifold and manifold to battery

What I've discovered about the car:
Previous owner spliced a new maf harness
Alternator harness has also been spliced

What i haven't replaced:
Throttle position sensor
IAC valve
Injector harnesses

mod list:
Jdm ej205
tgv delete
Aem 340 fuel pump
Bosch alternator 130amp
Cobb sf intake
Perrin turbo inlet
Nvidia turbo back
Tomei headers and uppipe
Vf39
Sti tmic
Phenolic manifold geometry dash meltdown spacers

I replaced the plugs and coils with NGK 1 step colder and diamond coils less than 5000 miles ago as well while trying to figure out this issue.

I also have a log of just the bucking but I'm not sure how to post it here.

What should I pay attention to when the controller has to operate for a long time?