Catalyt Failing On Error Code

[786lexus]

hi guys i have just noticed my engine management lights on, taken to my mate it it states that cat is not working right, maybe its worn out? he took the light off and told me to thrash the car for a while...... so £20 of petrol within a couple of hours and the car is fine again......until i start driving normal again at motorway speed and light turns up again!!!! damn!!! can anyone please donate a catalyt or forword me where i can find a cheap one? or any ideas other than taking out the engine management light bulb out? which i ended up doing on my previous car lol..... i can turn the light off but it keeps propping up again!

[Steve_D]

What was the fault code number? I cant find a catalyst error code in the database.

[yemgi]

There is P0420, at least that is one of the ones that appear on mine but the car is fully decat :P

[786lexus]

il let you know tomorrow when i take the code off again for the 4th time lol, can you do summat about it?

[D8driver]

P0420 error like Yemgi said is the most common. I don't think it's the cat but check your lambda sensors because every time I saw P0420 it was one of these failing.