i just got a custom downpipe made for my civic with 2 o2 bungs. some guy at a local shop told me that i shouldnt keep both of my o2 sesors. If i unhook one of them isnt that gonna cause a check engine light. My car is turbo and i eliminated the cat. I need more info

 

if you install both O2 sensors it will set the CEL also.
without a cat the car will see almost identical readings on the O2 sensors and set the cat code.
An O2 simulator is your best bet for the secondary (rear) O2.

 

Or a different ECU.

 

how much would the o2 simulater cost and where could it from,the place where i got my dp made just blocked off my rear o2 and told me just to cut it. Im running a vafc 2,dsm450cc injectors and a walbro 255 for my fuel managment on my setup

 

if you can run a soldering iron you can make one for ~$12.
http://www.mkiv.com/techarticl....html

If not, you can buy one for ~$30-40.
http://www.casperselectronics.com/
or any other one you can find with google. (search: O2 simulator)

 

thanks i bought the parts for it.