I have a 2005 Ford F150 with about 81,000 miles on it. Last winter I noticed that it was rattling pretty loudly from under the drivers side dashboard. The truck only does this when it is cold outside and stops this behavior after it warms up. It will also temporarily stop rattling by just tapping the gas pedal and revving the engine slightly from idle. I have posted a video on youtube demonstrating the rattle. Have a look at the video and let me know what you think. Any help would be greatly appreciated.

Thanks

 

You may be onto something with the brake booster. It's pretty easy to pinch the line shut or pull it off and plug it to test that theory. Just don't try to drive it like that.

 

Thanks, I will give that a try. Any other ideas?

 

I unplugged the vaccum line from the brake booster and it proved to have no effect on the rattle. Any other ideas?

 

I don't think its the engine vacuum level thats stopping the rattle, I think its simply the engine RPMs...

It appears that the idle RPMs are just exactly at the correct frequency to hit a harmonic and excite the vibration that you are hearing.

The great news here is that its at idle... should make diagnosing easier. With the engine idling, lay on the drivers side floor and start touching things till the vibration goes away.

It could still be the booster rattling... if it was the booster then stepping on the brake pedal would stop the vibration. Have you tried this?

 

Good point about the rattling stopping when you depress the brake. Currently, it will rattle if the brake is pressed or not. I have tried crawling under the dash with no luck but I will give it another try. Thanks for the help.

 

maputnam, I had this exact same noise in my truck. It always sounded as if it was coming from the driver's side of the dash, and it only happened at a narrow RPM range, but I could never find the source. Out of ideas, I checked under the hood. Everything looked fine but, on a whim, I decided to readjust the air intake tube where it joins to the driver's side fender. (Basically, I just pushed the tube into the opening and twisted it around to ensure it was seated well.) Since I did that, the noise has gone away.

I'm not sure if this will help you, but I figure it's worth a try if you're still trying to fix this problem. Good luck!

 

Has anyone figured out the the noise coming from underneath the driver side panel?

 

Check the bolt holding your air cleaner tubing going to the fender. Mine is missing the bolt and it rattles and sounds like its coming from under the dash.

 

This was the problem with me and that rattle

I did the gotts mod and the tube was actually just tapping the inner fender wall and made that exact noise. I even took it to the Ford dealer to try and find the noise haha.

Check your air intake tube. Take it out and see if the noise goes away that will tell you for sure.