I put in a complete Nismo exhaust system with test pipes, o2 simulator, everything except the manifolds. The system is very loud and very deep. After reving up and letting return to idle, there is a noise from around the resonator. The production is 4/04 and 2 DTC's keep popping up,po138 and po158. Looking for some feedback on my situation.

 

no body give me the answer??

 

wahts it sound like? i have helix test pipes and they sound like **** when not at wot and at low rpms. sounds like a rattle but its not. i think its just the sound of the fummes with no restriction. threw the car on jack stands and had a buddy rev it up while i was under it. wasn't hitting anything but the sound is comming from the straight pipes.

 

Dont know if it helps, but did you check for leaks?? On my old car the header to h-pipe connection had loosened and it sounded like i was dragging the exhaust system on the road behind me,it sounded like metal rattling, but after i tightened up the bolts it was fixed.

 

thank u.i'll check it