How to change the speedometer for 3-4 miles fast MK4 (Vag-com)

Jun 28, 2016
How to change the speedometer for 3-4 miles fast MK4 (Vag-com)
  • How to adjust the speedometer for 3-4 miles fast - MK4 VW


    Introduction

    The speedometer can sometimes be a little fast. Changing the Distance Impulse Number with the procedure, below, changes both speedometer AND odometer accuracy. A typical scenario with stock size tires is a speedo reading 3 - 5% high with a dead accurate odometer. Changing the Distance Impulse Number to correct the speedo error introduces that same percentage correction to the odometer so you wind up with an accurate speedo but an odometer reading 3 - 5% lower than before. The original intent of this adaption was to calibrate for different tire sizes rather than to correct the typical inherent optimistic speedo readout.

    An alternative correction method is to manually re-position the speedo needle at rest which preserves odometer accuracy while correcting speedo error, but only at a narrow range of chosen speeds (because of the linear correction of a non-linear speedo readout). This may be a better option if you object to losing odometer accuracy and don't mind the speedo needle sitting below "0" at rest or the narrow range of speed at which the speedo is accurate. See cluster removal and needle adjustment for that article.

    This is on stock tire/rims 195-65-R15.

    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]

    This is on stock tire/rims 195-65-R15.