Inner guard resonator removal sound

[Rubesube]

Hi all new to this club and have picked me up a stock standard98 s/tb forester and very keen on having a good play with it. Done a lot of reading etc and first mod on the list was the resonator removal to free up the intake a bit. Once done and reset the ECU I took it for a drive and noticed a strange sound like nothing I've heard before , which sounds like someone blowing air over the top of a bottle. It only happens while accelerator is down and seems to love the 2500 rpm mark and doesn't make the sound all the time aswell. Knock sensor and o2 sensor codes have shown up but were doing that before the mod. All VAC line checked for leaks by sight and ear. Is this normal until I fit a cai or is it something else?

Any help would be awesome.

Edited March 15, 2016 by Rubesube

[Fastfour]

Normal as.

[Leufkax]

Maybe instead of mods you should focus on actually getting it working properly first? Just a casual suggestion

[Joker]

George? aka leaky OEM bov?

[Rubesube]

Sensors sorted and mod only done as free and easy.The sound is strange as you can be cruizing at 100kms in 5th and once you get slightly over 2500rpm the sound will start and its a real drone of a sound with a bit of pressure behind it.

[Ajayy]

Induction noise?

[Rubesube]

I'll see what happens once I run the cai up the front and replace the sensors which turned up today.

[Rubesube]

put the first bend from the air box in and the sound still there but quieter,also replaced knock sensor and o2. The second hand o2 sensor must be faulty as still throws a code and low down power still jumpy az.