RedRedRed

I know that there a lot of threads about all the rattles and squeaks in C4s, but I’m looking for some help with a specific chirping sound that I haven’t seen mentioned in threads. I’m hoping someone has encountered and solved the same problem and knows what it is. It’s a rather high-pitched chirping that occurs whenever the car jiggles at all, not just over hard bumps. It seems to be in sync with the cowl shake, which means I'm hearing it all the time.

It sounds like it’s coming from somewhere inside the dash, but it’s hard to nail down. It’s not related to the top because it happens with the top up or down. I haven’t gotten under the dash yet to poke around, but I don’t even know where to start looking other than trying to find something that seems loose. Nothing on the outside of the dash seems to be loose. It really doesn’t sound like plastic, although I suppose it could be. It sounds more like some metallic parts rubbing together.

Dose this description sound familiar to anyone?

95LT1ZF

It sounds familiar for every 80's and 90's GM vehicle I've owned. I was able to eliminate the issue in my 98 Z71. I narrowed down the area by pressing on different areas of the dash while the squeak was occurring to see if pressure on certain areas made it stop. I narrowed it down to the center radio area and started there. I pulled off the cluster and radio bezel and tightened every nut and bolt I could find. That didn't help. I then bought a bag of Polyfil and jammed Polyfil everywhere I could, being careful not to cover any heat vents on the radio etc. I drove around with the bezels off and continued putting Polyfil in the dash until the squeaks went away. I am sure there are better ways to fix this, but this method worked well for me and only cost me $8.00 and an hour of my weekend. It also quieted down the AC operation and a few other things.

RedRedRed

Thanks for the advice. I'm not familiar with bags of Polyfil. Where do you buy it, and what form does it come in? Is it pellets of foam? How do you get it to stay where you put it and not work its way out?