hey guys i got a 94 civic ex and i have had loud noises coming out from the front and under the car .. i think its the exhaust manifold .. if i change just upgrade the headers would it solve the problem ??? also my engine check lights comes on occasionally .. would ne one know wats hte problem? is it the oxygen sensor???? also does nebody got ideas on wat kind of catback exhaust would look nice on a 94 civic and not be too loud .. thank you very much