Troublecodes 2.0 Vvti Help!?

[Lid`en]

This weekend I was on a long trip with my 2002 Rav4, its a 2 litre Vvti gazoline engine, about 180000 km.

I was driving in a long "tunnel" about 11 km long ( yes we do have loooonge tunnels here in Norway :) ), then my enginelight ( MIL ) light up, the engine was at normal operating temperature, about 3- 3500 rpm`s and no particulary load on the engine ( flat driving ). I dont notice anything on the preformance on the car so I continue to drive home.

Today I read out these toublecods wit a OBD II tester: P0420 Catalyst system eficiency below threshold bank 1

and : P0430 Catalyst system eficiency below threshold bank 2

Can anyone help me figure out what these means? ( I figured that maby the bad air in the tunnel could cause the engine to get to low oxygen intake and therfore maby not good combustion? ) But maby anyone else has had these codes before?

I erased the troublecodes today and drove home from work, no MIL light now

( extra info: One of the lamda/ oxygensensors has been replaced fore about two years ago, and I have had a MOT test on the car for about a month ago and the exhaust was clean: CO: 0,02

HC: 16

Lamda: 1.006

Hope anyone can help me? :)

( and sorry for my bad english )

[PhilGee]

Probably the cat on its way out. The engine management system is quite sensitive so if any of the running parameters get close to the upper or lower limits then you'll know about it. Even doing an emmissions test probably wont pick anything up. Best bet is clear the codes and see if it returns.

[anchorman]

Eventually the light will come back on. The Toyota fix is for a cat and the oxy sensors but I've known a car with these codes to run for years and pass the annual test. You might need to learn to ignore it!