Problem With Free-Flow Converter

Listen, here is my problem. I just installed a free-flowing converter on my 1998 Honda Civic EX. I have a cat back PaceSetter exhaust. Until I installed the free-flow converter, everything was fine. But when I installed the new free-flow converter, it tripped a code to the CPU. What I am wondering is, what can I do to get the CPU to not throw a code. I do know now that there is not enough back pressure to the engine. Hope someone can help me on this one. Thanks