Is it really necessary to have a by pass valve for a cold air intake??? I heard that it only work when the inake is completely underwater and im not planning on driving my civic though water or driving it while its flooded.

 

No.

 

no but it is cheap insurance...i mean it depends where u live...like here in FL it could be bright and sunny and you come outside your job 5 min later and a monsoon has come andleft 3 feet of water around your car...

 

yeah, it all depends on where you live. in sacramento, there are puddles everywhere when it rains, so its a good idea. but if i were to move to Reno, i wouldnt even bother.