Code P040

[mr2grfe]

Hi,

 

My 2008 Aurion is throwing code P040.

It's annoying because it trips all lights on the dash.

I can clear it but after a few hundred ks it trips again

I've been told it's a cat.

I was hoping to get help on specific diagnosis and repairs.

Screenshots from OBD2 attached

Many thanks

[mr2grfe]

My it could be a cat or a oxygen sensor. Nobody knows

[Tony Prodigy]

If you're  handy, remove the cat and take a look inside to see if the mesh screen is obstructed and give it a clean anyway so it doesn't have to be done later and see if this cures the issue.

From what I see in the data, It seems that the issue stems from the downstream section, hence my suspicions about the cat. It's throwing all the upstream hardware into chaos.

[campbeam]

What is the odometer reading? You can try cleaning the downstream O2 sensor [B1S2]. This worked for me years ago. A few YouTube videos recommend that it is more economical to replace this O2 sensor especially if you are not DIY. Good idea to also clean the MAF sensor and the throttle body.

Now the P0420 code has reappeared on my vehicle together with a slight misfire at idle. So been busy for the last few weeks trying to resolve this specific issue particularly that misfire. At this stage, the P0420 code is re-appearing within 20 kms of driving which is obviously not right. I will soon find out this coming weekend whether I have finally got the right fix.                        

[campbeam]

This YouTube video appeared and after viewing I have ordered 3 of the intake plenum gaskets.

https://www.ebay.com.au/itm/275736040954?epid=28048759897&hash=item40332615fa:g:eLgAAOSwTDRhHGb6&amdata=enc%3AAQAIAAAA4NFsnYDfH6g6tlLLuEGpuFECCcx%2F%2F91%2Bune362W1spgGPwzW%2F9lsQav7v0WTG%2FJylQsl4q1tWaxQz4I%2BHGQA01Z6C4mTNgsIty7pdXOP7%2BpZ1DQDeVS7E%2Bw7%2B3g3RjthaUOYvwS0%2BIGDIT2Z1z36VF7zbyACSujKik%2BfKun5J7QmOmSvNyPht0RF2hK3jAmu9A2dVmlkG7pS4Y3wd%2BcbwfaqCwtOztmGpA54ukn6%2FVwciPEiaw5G8dFR%2Ff1jsVZHahBgBA6Ce7fyURCAT7wzte4IIk5E7yUj1C0uRtSkUn71|tkp%3ABk9SR4iVyNOwYw