Frist gens come with two O2 sensors, recently one of mine has gone out, I was wondering..what are the disadvanteges of running one O2 sensor instead of both...and how(where) do I connect them together?

 

motor runs better with both, one in each set of primaries....some dummies run them with NO sensors or only one...there is a conversion to running a single one but many builders do not recommend. i am happier with both with my modded PR3 ECU.