Ok my car has an offroad exhuast, no cats of any kind on it. Every now and then my check engine light comes on on the dash, when the car warms up (but will go off even when ive run the car for hours sometimes) and the previous owner said it was due to the 02 sensors. Im guessings its the downstream ones and they are fouled out because im not using cats. However, if i put new ones in, will it do me any good? Wont it throw readings at the computer like my cats still are'nt working and put it in limp mode like it does? Advice would be appreciated.