Warning:
Never do this with an engine low on oil, coolant, has a serious knock or known bad rod, etc, etc.

A serious issue is that long term short distance inner city driving can cause = engine to not reach operating temperature = depositing coke/carbon, and fouling the engine prechambers + valves = this is abusive commercial use = consult your owners manual for corrected service intervals.

An Italian Tune-up can help blow accumulated coke/carbon/fouling out of the engine.
Valve adjustment is called for every 15,000 miles for the generic average driver = consult your owners manual for corrected service intervals.

Valve adjustment OM617 FYI.
Valve adjustment OM615, 616, 617 FYI.