You can remove it, but you'll need a tune to get rid of the fault codes. It wont effect the way the car runs in any way. You just need blanking plates for the rear of the cylinder heads where the valves go in.
I've done it on rally cars before.
I doubt any cops would know that it was missing if it wasn't there.
So it shouldn't be a problem.
But if it's still working just leave it.

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Its just the internet dude, its not real.
F.B. Racing
01 WRX (STI badged)
2010 XR5 Focus
06 Impreza Hatch 2.0i

its the air pump thats making the noise not the valves, the valves do fuck up alot and are expensive to replace. so removing them and the air pump would be worth while move

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Marti


Car: C Red S13 Silvia 2.3l 400+rwhp-SOLD
Daily ae82 4age corolla (light mods)-Sold
Daily:SWB GQ Patrol
Will be a 03-04 STI next

That noise would s%#t me big time.

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"ALLPAWS" 2014 WRX RS 40 - modding very slowly.
2002 Mitsubishi Airtrek Turbo R - Ralliart Edition (daily)
2010 Nissan GT-R - when the Missus let's me drive it :)
Crotch Rockets . . .