Downpipe Question

[Romogst]

Does the check engine light will come on if i buy a new downpipe with a high flow cat converter?? What steps should i take for the light not to come on. Do i just put the O2 sensors back. I got a 99 GS-T.

 

[zac83]

answer: yes... reason: inaffective cat it will show that your cat isnt doing anything between b1s1 and b1s2....

 

[UltraImports]

Hey Romo, I go up to Warren often, my gf is from there. Are you part of the Speed People groupies? I know they have a following up there.

 

[larryd]

Originally posted by zac83
answer: yes... reason: inaffective cat it will show that your cat isnt doing anything between b1s1 and b1s2....

actually its a tossup, I put on the Apexi n1 downpipe and catback on both my GST and my GSX and I havent had a CEL on either of them. the cat is replaced with a testpipe on both my exhausts.

Some cars will trigger the CEL and some wont.