Just put a DC header on my car, And when we changed the o2 senson to the differant location, i think we may of messed it up. Now my air fuel gauge doesnt respond, and my car bogs down sometimes, and it will throw a check engine light but when i turn car off/on again it goes off, but still bogs.. I also got a full exhaust put on 2" from header, no cat on it..So im guessing im 02 is bad for 1, and backpressure could be wrong also, but I dont think that would do too much to it.Everything else I have worked fine until i got header/exhaust so it has to be the o2....
