Originally Posted by wavehogger

I'm not so sure that the problem is 100% truely solved. It may be that like in my car the noise is a little softer at times and then occasionally gets a little more noticable. If changing the ECM didn't totally resolve the problem it could be something else making the noise. Or all the ECM's are going to make the whine, some just more than others. Replacing could be a gamble, where you'll get a quieter one or maybe even louder.

With that said, I took some time today to try and trace it and it seems to be coming from the back of the car, not under the glove box where the ECM is. With my head under there and with the glove box out it's silent under there. I wonder if it isn't the fuel pump since I've heard a few of those whine over the years. They usually sound a little more mechanical and this noise is more sine wave-ish as someone else here said. If it is electronics related, are there any other electrical components in the back that could be making the noise? And maybe there are two noises happening here, and that's just really sad. I'm going in for service Friday and mentioned that I want them to look into it, though if we don't have answers here, they probably won't either, lol.