P0491 Code Only

[gillara]

Hello all,

I keep getting a P0491 code on start up and I usually clear the code and goes away after driving.

After doing some research on the forums it seems like it could be the air hoses running behind the engine that come loose, however that is not my case. All hoses are properly connected.

Any ideas? I am planning on removing and cleaning/replacing the O2 sensors, but I am running an Alpine stage 2 tune so not sure if it would help.

thanks