How does a bad mass air flow effect the running of a diesel?
Dealer says my car is bringing up a defective code for the mass air flow.

You didn't give us a year or a model or your location, so I must make some assumptions in order to reply. They are that you are in the U.S. and have a 1996 or later E300.

The fuel/air mixture in the engine is computer controlled. One of the things the computer needs to know is how much air is coming into the engine. That is the information it gets from the Mass Airflow Sensor. Mine is still working fine at 4 years and 90K miles, but I have heard of numerous failures.

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Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
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