Engine noise solved! It was nothing I did, just too much gain on the amp...turned the gain back some, increased the signal from the pioneer head unit to the amp to compensate and the added a ground loop isolator and man it fixed it perfectly. All is well with the entire system. I am SHOCKED at how the front bose speakers kick as after adding an amp to drive them. I have Kenwoods to put in there, but man I almost hate to take these out, they rock with 60 watts rms going to them. The difference in sound between that factory amp and the MB Quart amp driving them like night and day.