P0420 engine management 1.6 psi

[Carltaff]

Hi All,

have recently changed my cat after getting the P0420 code come up , went for a sports cat after pricing compared to audi, (cat was gone).

Car was fine for a few days but upon my return from rally GB last week the same code came back on, 2 1/2 hours of driving back at 60-70mph.

Could it be the lambda sensor on the new cat? or would you be thinking exhaust leak? (cannot hear a leak)

Many thanks

Carl

 

[a2sumo]

I may be completely way off here but are we talking about the cat looking box under the car ? If so I think it's not a normal cat I think it's designed to take out excessive "nos" due to the stratified charge. The cat is on the manifold in the engine bay.
Not sure a sports cat would be suitable - I hope I'm correct but happy to be educated. Cheers Mike

 

[fbi]

I think it does both : "regular" catalytic reduction + NOx trap (storage then "regenerate").
Anyway, like Mike says, that's a special device.

I have seen that some aftermarket "sports" equivalents are available though (I mean elements to be used by exhaust builders).

 

[Carltaff]

it is the one under the car correct, went for a new build by a reputable sports exhaust company, next port would be the lambda sensor i think