2011 wrx breaking up at 4500rpm only

[erisrusnac]

I have a 2011 Subaru wrx (ej255)
When doing a wot pull in any gear from 1k to 4500rpm it’s fine but at 4500 it breaks up almost like it’s misfiring or like I’m releasing the throttle or bouncing off rev limiter.
But if I slowly go past 4500rpm to 5k and wot it runs great to redline.
Its the worst in 2nd and 3rd gear
If I shift from 2nd to 3rd at redline and the rpm’s drop above 4500 it doesn’t happen and runs good.
I’ve done
Spark plugs, coil packs, MAF
No codes
No CEL
TLDR: car runs fine before and after 4500rpm but breaks up at 4500rpm.

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[rtv900]

you gotta get a video of this man
way too subjective what "breaks up" means

[erisrusnac]

https://youtu.be/7dsRxZOlhjw?si=hXBPnl1PmvaGxqAq

Since previous post I have replaced
Fuel pressure regulator and upstream o2 sensor

[Mauled]

Your plug gap is too loose, tighten it.

[KatherineESmith]

Originally Posted by erisrusnac

I have a 2011 Subaru wrx (ej255)
When doing a wot pull in any gear from 1k to 4500rpm it’s fine but at 4500 it breaks up almost like it’s misfiring or like I’m releasing the throttle or bouncing off rev limiter.
But if I slowly go past 4500rpm to 5k and wot it runs great to redline.
Its the worst in 2nd and 3rd gear
If I shift from 2nd to 3rd at redline and the rpm’s drop above 4500 it doesn’t happen and runs good.
I’ve done
Spark plugs, poppy playtime chapter 3, coil packs, MAF
No codes
No CEL
TLDR: car runs fine before and after 4500rpm but breaks up at 4500rpm.

Diagnosing the root cause is essential to ensure optimal performance and prevent further damage to the engine.