Hi John

While the GTi group seems to believe that shifter shake can be fixed through
adjustment, I believe that poor development is the underlying cause of this
fault rather than poor assembly...

Locate the control cables going into the gearbox, from the center of the
firewall to the driver side of the car (left hand drive).  The cable sheaths
are wrapped in silver (heat blocking) foil on my car.

I estimate the free length from the firewall to be about 12 inches.  Find a
piece of rubber or plastic hose with 3/4 or one inch internal diameter, the
softer the better.    Cut two pieces about 7 inches long and slit them down the
length.  Place one piece on each cable sheath by opening the slit.  [If only
hard hose is available, cut it almost through to create two or three connected
pieces]

Position the hoses approximately in the middle of the free length of each
cable, and wrap with masking tape - save the duct tape for once you have found
the best length, if this works at all.  Tape the hose to the cable only at the
top so that the other end can slide if it wants to.

The added mass in the middle of the cable will drop the resonant frequency,
possibly so that shaking stops or moves to a less annoying rev range.  The
friction between the sheath and the hose will damp vibration in the cable and
should reduce the amplitude of vibration in the shifter.

If you find that the nature of your shifter shake changes with the above, but
does not go away, try reducing the hose length by two inches.  If this is not
to your liking, try using 9 inch pieces of hose - you want mass and friction to
damp out vibration.  A hose that makes the cable rigid from end to end will
probably increase the coupling and not improve matters.

Good luck - please let me know what you find.

Peter

pfellinghamrgi  [work]
dynosorgte  [home]

"I recently discovered that my '96 GTi has an evil buzz seen and felt in the
shifter on a trailing throttle from 4500 RPM in first gear.  I suspect this has
come about after my shifter was reset to factory spec to improve shift feel and
reduce
slop.

There is no way that the whole drivetrain is thrashing back and forth at
that frequency and amplitude.  Just thinking about it, I bet the buzz is
caused by the cables resonating (flapping about) at a certain frequency
(RPM) depending on the tension in the cable.  The tension would depend on
the gear selected and would change as the engine rocks back and forth on its
mounts when you open and close the throttle.  Once the flapping starts it
seems to be self sustaining until the revs have dropped below 2000 RPM.

For those of you who see shifter shake as an unacceptable problem, I bet
that taping something flexible but somewhat heavy (like 1 foot of thick
walled rubber hose slit lengthwise) around each cable would change the
shifter shake so that it moves to another gear / speed / load.  The
appropriate damping is sure to stop those somewhat unsupported cables from
flapping about.

Will someone who has been diagnosed with terminal shifter shake please try
the above and call me in the morning..."

>Hmm.  Then why do some cars have it while others don't?   The only time
>my sifter shakes at all is if I give it too much throttle at very low
>(like less than 1750) rpm (especially in 2nd and 4th) or if I go over
>mongo bumps, especially in neutral.  My shifter is rock solid the rest
>of the time.  I do recall that my shifter moved a bit more before I
>installed my Whipple Mount, but still not like some of these people
>describe the problem.

Hi Uwe

I'd like to bet that a significant proportion of GTi's do have some shake at
different speeds in different gears.  Its not reported because the driver is
too busy watching where he is going or the sequence of normal driving does not
provoke it.... With my car, it only happens in first gear on a trailing
throttle from 4500 RPM and up.  How often do you mash the throttle in first to
high revs and then lift off the throttle without shifting - in an autocross
maybe?  Otherwise, you usually shift to second as you throttle back, and may
never notice the shake.

The interesting thing is that it seems to occur either at full throttle or
closed throttle, never both.  This says it has to do with the engine position
as it rocks on its mounts - hence the change with your new mount.  The
"unsupported" length and tension of the sheath is probably not specified very
carefully by VW.  Only the position of the gate relative to each gear detent
matters to them.  To me it seems that it is the variability in sleeve lengths
and support, from vehicle to vehicle that gives the shift "linkages" a spectrum
of resonant frequencies.  This would make setting the gate "correctly" to get
rid of shake near impossible in all cars.

I think that if the unsupported cable length and tension in the extremes of
engine rock and gear selection were controlled more tightly, we would have a
chance of finding a cure-all solution.  For instance, your shake is when the
cable is slack: engine rocked back by in second.  Mine is when the cable is
tight: trailing throttle in first.  No one setting of the selector is going to
fix that and all combinations in between, but appropriate damping of the cable
just might.

Peter