Visitor # 57250 since 19.SEP.2001
Does your Odometer click every mile? If so, chances are you have a very common problem with VW odometers. Look for a detailed writeup on this fix on "Jan's VW page". There are detailed instructions on a fix there. Howeve, lets for the sake of this discuussion, assume that the problem is with the main spur gear that is driven by the worm gear that is cracked. It is a press-fit nylon gear on a 3mm shaft, over time, the plastic fatigue and crack from the press-fit. As the worm teeth passed the crack, the crack will expand, allowing the worm gear to slip past the spur tooth (i.e. click!). One might be tempted to pull the spur gear off the shaft, ream out the hole to 1/8" (a shade over 3mm) to relieve the stress, then used some activated/catalyzed super glue to glue the gear back onto the shaft. With the larger hole, stress of the press fit is relieved allowing the crack to remain closed and the glue now holds the gear to the shaft instead of the press fit (which led to the crack in the first place).
You can see the steps involved in the images below. The speedometer can be removed from the instrument cluster by removing the screws that hold it in place. Then, remove the two screws that hold the back plastic cover and look for the worm gear/spur gear combination that drives the odometer. If the spur gear has a crack, that is the source of the skipping.
Broken odometer drive gear
1/8" drill bit to enlarge the 3mm press fit hole
Odometer gear reattached with plastic cyanoacrylic glue
Cost:
$3 for some plastic-compatible super glue
Rating:
-- (it depends on how hard you need to work to get to the odometer)
Note, the stock VW odometer drive gear is 21 teeth, at least on the A1 models.
[Last updated: 13.September.2021]