About 6 months ago i decided to take off my catalytic convertor and just added a pipe whilst still taping in my secondary O2 sensor. Well didn`t notice MUCH differnec in power but whatever .. everything went ok, and my 02 lamp didn`t light so all was fine. Now after leaving my car in the garage (haven`t been usin it much) .. when i started it up .. my Sec o2 sesonr light came up! .. when reving the gas however it sort of faded off again .. but came back on just as i released the throttle. Now .. is this normal ? Maybe they`re some water or carbon deposit on the sensor since i haven`t used the car much ? Should i reconnect my catalytic ?? Help .. any thoughts about this ?! PS: I still didn`t have time to give the car a run ... i just reved it in the garage.