Problem on my Garmin Instinct 2

4558632 said:

differs to 100 steps in a 4 meter distance

Are you telling the watch counts 100 steps when you walk 4 meters (normally some ~6 steps)? That would be indeed strange, unless you walked very slow and have been shaking the hand wearing the watch in high cadence, or were experiencing external vibrations (quake, engine,...). If there were no such vibrations or shaking, then I'd recommend contacting the Support, the device may be defectuous..

If in contrary, you mean that the watch shows 4m too short or too long distance when walking 100 steps, then you may need to calibrate the counter with a GPS measured Walk activity. Have a look at the documents: 

• The Step Distance Recorded on My Garmin Watch Is Wrong 
• Improving the Step Distance Accuracy of My Garmin Outdoor Watch 

4558632 said:

still counts steps when driving

The car either needs new suspension, or you have to disable the steps counting for example by starting the Indoor Cycling activity - all cycling activities disable the steps counter, but the indoors cycling has the advantage of not using the GPS, hence not significantly increasing the battery consumption, and not automatically falsely increasing the cycling distance. You can discard the activity at the end, or save it and changing it to Driving later in Garmin Connect, if you want to keep the record of your drives.

Highly inappropriate to make jokes about Parrkinson's disease

NoTrux said:

Highly inappropriate to make jokes about Parrkinson's disease

Unfortunately it is not really a joke. I have a friend with that disease, so certainly do not take it light. However, uncontrolled shaking, whatever the source, would be the only explanation of having 100 steps recorded within a few meters of walk. It is in no way told to make fun of the disease. Another option is a defectuous device.

I know people, including family members, who have died with Parkinson's.  It's an inappropriate joke.  You can't cover it by making a serious turn; there were lots of other things you could have said, but it was beyond obvious you were going for a highly offensive joke.

I apologize to anyone feeling offended. I'll edit the original post.