I had my subs installed at a profesional shop because I don't have an aftermarket head unit so they had to rig it up but it has alot of engine noise coming through it when I have the Gain and Freq where I want them to be. How do i get rid of this? Any ideas?

 

Go back to where it was installed and tell them to fix it. It's their job to have it working properly, so don't feel bad about asking.

 

Damn right, you paid for it to be right...go make em fix it.