Most O2 sensors require a certain amount of heat to operate! They have to get hot to get an idea how much oxygen and spent hydrocarbons are in the exhaust. Read the instructions that come with the installation kit! Remember there are certain methods of sealing these into their threaded rings. No teflon tape, R.T.V, Anti Sieze etc. Read the instructions, they change them every day to make lazy mechanics look like the fools they are!
