Whistle From 1.6Vvti At 4000 Rpm Under Acceleration

[t25gary]

Hi all,

I have a 04 1.6 avensis and lately there has been a strange whistle noise when I hit 4000 rpm under acceleration, also the EML has come on and says catalyst bank 1 on the diagnostics, could this possibly be a leak in the intake after the airflow meter which is throwing out the lambda/oxygen sensor readings and causing the light to come on? It's driving me mad now at this stage so any help would be greatly appreciated! :)

[Raistlin]

Obvious, but check for air leaks, Silly question but have you changed your air filter recently ?

[t25gary]

Obvious, but check for air leaks, Silly question but have you changed your air filter recently ?

Ok so I should check between the air box and the manifold? Yeah I changed the filter there about 3 weeks ago when I serviced it,

[Raistlin]

Was it a Toyo part or someone else's as that might let air rush in if it does not fit snug.

Did the noise appear since you changed the filter ?

[t25gary]

No its a spurious filter, it came on half way through the last service, out of no where and the whistle exist for a good while, but its been the same type of air filter ive put in since I got the car,

[t25gary]

Ok I've established that the whistle is coming from the exhaust, could this possibly be the catalytic converter that's blocked?