Fault code P2196 Oxygen sensor?

[Saphe]

Originally Posted by SirDigby

that makes sense because the engine runs richer at cold start up. if the air filter was really dirty it might throw a rich fault. an incorrect signal from a dirty MAF sensor may cause a rich condition. a leaking injector could cause fault. this is what i would do:
check condition of air filter. if it is dirty, replace. wile at the auto parts store getting filter, pick up some MAF cleaner. (Mass Air Flow) the MAF is the sensor that is in the air box you remove to change air filter. remove the 2 bolts and pull sensor up. clean with MAF cleaner. allow a few minutes for cleaner to evaporate before reinstalling. i would also replace the A/F sensor. it sounds like it might be lazy. they do wear out. don't buy from the dealership, too expensive. BUT, only buy Denso, (234-9052) Toyota,(89467-52020) or NTK (24661) brands.

Thanks SirDigiby.
I started with cleaning and clearing the sensor connectors with Electric cleaner and this without successivt. No Light came on my way to work (25 km) but driving home did Light it up after 20 minutes of driving :( i dont get any symptoms more then check engine light. My thoughts has also been on looking into the mass Air flow sensor so i will do that and check the air filter. If still the problems occurs then my last step will be buying a new a/f sensor - toyodiy homepage gives me part number 89467-52070
I will se if i find denso in first hand before looking at other producers :)
Thank you for your advice :) i will be putting in the outcome when im done. Will take a while before reposting :)