p-0240 code- trying to fix.

i've got a 2003 camry. With the 4 cylinder engine in it. And i've got a p0240 code.



I've change the 2 o2 sensors. along with the piece of exhaust from the manifold to the resonator with a brand new piece. And light came back on again.



I think i'm going to change the manifold now which has the second CAT in it.



Do you think there is any things i may be over looking?



Thanks