Resonate clatter at 3,800 RPM

[Wayne Cox]

At 06:39 AM 5/22/2003 -0500, you wrote:
>It happends under load or in nuetral .... it only makes the sound at this
>one rpm range. If I rev the engine to 5k or so and let the rpms fall, like
>clock work the clatter happens around 3,800 and then imediately stops
>again. Any ideas?

Sounds like a rod bearing knock to me  :(  They're rpm specific like
that.  Plenty of talk in the archives, but the basic diagnosis is remove
the plug wires one at a time (so it's running on 3 cylinders, and one is
unloaded) and see if the noise goes away.  Try starting with #3.

I'm not sure if it's safe to pull the wires with the engine running (ie -
and not get zapped!)  I've always shut it off to be safe.

    -Wayne  91 NK2k,  93 NX2k,  92 SE-R-Parts-Car