hi all right i have put on a decat down pipe and now the Check Engine Light
comes on is this the 02sencer if so how do i get a round this
many thanks it is on wrx 2004

 

Most likely p0420 code mate.

Only way around and to make the most of the decat is a re-map.

Steve

 

ok thanks i think i will take the battery of to reset the ecu

 

taking the battery off is not a re-mapp, why do you want to take the battery off, all that does as you say is reset and clear the codes, the cel light will come on again if the ecu reads an O2 fault

 

I have the same problem, fitted a japspeed sports cat. Thought it would be ok. Will it damage the car running with that fault, suppose its the reading on lamba sensor.

 

Ive noticed on the newage cars compared to classics that the ecu seems to be a bit more sensitive. I fitted 3" decat system with snake head downpipe to classic and it was fine for the week until the simtek was fitted, then fitted a simalar system to a newage and it would throw the cell light on everyday untill it was mapped.