O2 sensor replacement help - which side is bank 1 and bank 2

[Leftfootwonder]

Hi all,

Got the P0421 and P0431 codes thrown up recently on my '06 Cayman S. I'm going to tackle them myself to save on labour charges but after a fair amount of googling, I can't determine which side is bank 1 and which is bank 2!

I'm also aware there are 4 02 sensors, would these codes mean changing all 4 or are there other codes for the other two? Tempted to just change them all, but if I can get away with spreading the cost now holiday season has arrived, it will!

Last question, do I need a special tool to remove them as I have seen some people use or can I get away with a normal spanner/socket?

Thanks in advance for your help.

[Rocket.]

Sadly can't help you there OP but recently had one done on near side of my 2009 gen.2 S, be aware that there is a good chance if you can actually remove the 02 sensor then it's easy to damage the thread, specialist did mine and had retap sensor holder/mount which meant fully removing the manifold, at this point you can be into a whole world of pain with broken studs etc. Forewarned is fore armed and all that. Good luck!

[Leftfootwonder]

Ouch! Thanks for the warning!