So I have a '99 5spd cali spec. I've done a fed conversion and in doing so I put on a fed cattman y-pipe and deleted the front two o2 sensors. So I now have a CES light going.

If I were to install a '99 5spd fed spec ecu, would it clear the CES light?

 

i believe so, not sure how that would affect the operation of your swirl valves, however.

 

I would delete the swirl valves, similar to how they do for the 00vi swaps. Or possibly do a 00vi swap and swirl valve delete while I'm at it

 

doesnt the 99 fed spec have swirl valves too??

PM IIyak, he did the full fed spec conversion from cali. He knows.