With my hardtop on, I get a booming/howling noise from about 2800 to 3000 rpm.
This is true even when revving the engine in neutral, so I know it's not the
If I open the bonnet and listen and feel the engine when revving it, nothing
seems wrong. I guess it's just the entire body cavity resonating. I have
checked my engine mounts, exhaust mounts, etc. and they all seem fine.
You should try the revving-in-neutral test to see if it is the drivetrain.
Also accelerate to a high speed on the freeway, put it in neutral, kill
the engine, and coast down to a reasonably slow speed. If you
have a driveshaft problem it will be obvious (the usual 50mph howl).
At 03:45 PM 3/2/2006 -0500, Tburke4@aol.com wrote:
>Our 1980 Spitfire is making a noise/vibration that seems to be speed-based. I
>can't say at what exact speed as the speedo has decided to take a little time
>off, but it occurs at 3000-4000 rpm in 4th. It is really a vibration, but you
>hear it moreso than feel it. It's probably been there for a while, but with
>the hardtop on, I can hear it better.
>The noise is like a loud, very low hum, sort of like feedback from a
>sub-woofer, loud enough to make conversation difficult. I suspect the
>(which I replaced with a used unit a while back, previous unit had a serious
>vibration @ 50mph) but before I pull it and replace it (again), I wonder if
>else has encountered such a problem and solved it somehow.
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