Another air pump question
 

I just took the air pump off my car and replaced it with a pully and now it seems the lower of the two pipes it was hooked too has the sound of an exhaust note. Is this normal??? Anyone know how to remedy this???

Thanks

Elliot

When I eliminated my air pump I put a 1/2 inch crankcase filter on that pipe and it muffled the sound to a negligible level. I'm not sure of the actual cause for the noise though. Perhaps someone here with a little more experience could enlighten both of us.

I think i'll do that. Still would like to know what purpose it serves.

still running the main cat?

I'm not running the main cat , and I put a cap on that pipe , is that a bad thing?

no but you should block off the ACV.

I blocked both of the pipes off .