Hi Im pretty to to modding of imprezas. I am thinking of fitting a decat pipe to replace the second cat and fit a straight through center to my 2004 wrx wagon. I think there is a sensor on the cat and wondered what happens to that with a decat and if i need a remap with the decat so i don't do any damage to the engine? Hoping you guys could help.Thanks Jon

 

if you have a cat back zorst you wont need a remap its when you take the downpipe off it needs a remap because there is sensors in the downpipe therefore makes the ecu go crazy

 

The rear sensor is in the rear cat so removing that will throw up a CEL code. Will need a remap to get rid of the fault but you might as well get it properly remapped at that time.

If you are local to Cambs I can switch the CEL code off for you.

 

Thanks that good of you. Im not to far away from cambs. Will it damage the engine at all just turning the warning off? I havent got it fitted just yet so i will have to pm when i have. Cheers again

 

Nope - it wont damage it. The only danger to the car is that by removing one of the cats that it will overboost slightly.