1100 RPM Dash rattle

[BrianX128]

This is driving me nuts. It's easy to ignore with the windows down or music on or something but it's 94 and miserable out and with the ac on I heard it all day running errands.

For whatever reason at exactly 1100 rpm "something" plastic ish sounding is vibrating and I can't locate it. It's not from the engine bay and my throttle cable isn't hitting anything either. I tried making sure the dash bolts I could find were tight, and that nothing in the glove box or ash tray were vibrating and still nothing. Noise only follows engine rpm, not gearing or movement.

It's extra frustrating because it's one of those noises where it's going to be something stupid easy that you push against and laugh about when you figure it out, but I am stumped. I can't even tell what side of the dash it's coming from it just sounds like it's right in the middle of the dash. That's a terrible description I know..

Someone else on this forum had told me on another thread he was having the same thing so I'm curious if they ever figured it out. Can't even remember who it was it's been a while.

 

[79jasper]

If it's a obs, look at the dash mounts.

Sent from my SAMSUNG-SM-G935A using Tapatalk

 

[F350camper]

check to see if your hood release cable is touching the engine in some odd way, like an AC line or any part of the motor.

 

[hce]

Change the timing, this will cause the frequency of the engine to change, hence moving the rpm of the rattle.

 

[hce]

Here's a real answer, even though timing will change the behavior of certain rattles, check the trim around the windshield. If loose it will vibrate against the glass.

 

[BrianX128]

Here's a real answer, even though timing will change the behavior of certain rattles, check the trim around the windshield. If loose it will vibrate against the glass.

We might have a winner here. The trim on the outside edge of the drivers side of the truck seems a little bit loose over there so I'm gonna try clear caulking it and see what that does.

 

[hce]

We might have a winner here. The trim on the outside edge of the drivers side of the truck seems a little bit loose over there so I'm gonna try clear caulking it and see what that does.

folded up pieces of paper stuck between trim and window makes a temporary fix for diagnosing.

 

[IDIBRONCO]

Maybe way out in left field but does your truck happen to have headers? If so, check the left side header. It needs to be "clearanced" or else it will hit the rear oil cooler cap and one mounting bolt. My 1985 F250 had this problem when I got it and it drove me nuts before I fixed the problem.

 

[FORDF250HDXLT]

9th Gen F-Series Dash Repair