Sticking Tach

[Hal Taylor <taylor@xxxxxxxxxxxx>]

The Tach in my '86 spider is behaving very strangely.  It seems to stick
at whatever point the engine comes under load, and then won't climb
until I lift my foot off the gas.  So, if I start from a full stop, rev
the engine to about 2k and release the clutch, the tach will sit at 2k
until I take my foot off the gas for the next shift, at which point
it'll shoot up way high, then come down and stick wherever it is when I
put the engine under load in the next gear.  It doesn't stick if I rev
the engine with the clutch depressed.

This can be kind of disconcerting, when I hear that the engine
approaching redline, look down to see how much room I have left, and the
tach is sitting there at 2500 rpm...

I remember previous threads about bent needles causing sticking, but it
doesn't look like it's all that close to the surface of the gauge, and
the behavior would seem to me to indicate something else...

Anybody?

Thanks in advance.

Hal Taylor
'86 spider veloce "Strega"
Venice, CA (Hi Fred!)

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