It's electronic. I can't see any reason why it should be making this noise.
Since it's behind a plastic cover and the cluster panel, the sound would be
impossible to localize. I'm guessing the cause is something in the engine
compartment (belt maybe) that just happens to be transmitting in such a way
as to sound like it's coming from the cluster.
I thought belt or some sort of vacuum leak but I (and two mechanics) can't
hear anything under the hood.
If I stick my head beneath the dash, however, it's loud and clear. It's
definitely inside the car.
OK, this makes more sense now. There are two ways that rev-related noise
could be getting inside the car that I can think of off-hand. One would be
through the clutch linkage if it's a manual. The other could be through the
throttle cable. Wonder if there's a loose grommet in the firewall?
Which leave two candidates in my mind: the throttle linkage and the
transmission control cable. If either one is loose, it could make a noise.
I'm not saying I feel confident that's it, merely I can't think of anything
You might want to pose your question on the alt.autos.ford newsgroup.
There's a lot more technically savvy people there, and that's where I go to
post any advanced questions I might have.
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