Had the same problem with my Ml 320 about a year ago, changed the o2 sensors as well as masss airflow sensor and not doing it anymore. must admit the car still isnt perfect though does still hesitate to much on acceleration but at least not like it used to.

engine used to die and then come back after minutes rest. sometimes two three times in a row, sometimes not for a month or two.

good luck

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'99 Ml 320 130K Miles
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