I need some advice on what to do with my '96 W140 S500. It started running rough and the Check Engine Light started flashing. I took it to a shop and they said that the diagnostic codes indicate a malfunction of the Mass Air Flow Sensor. The cost for the part alone is $550.00. They said that they would replace it and that would not guarantee a fix.

What else could be causing the error codes, dirty air filters, etc? Should I take it somewhere else?

Please advise.

Thanks,
Mike

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Mike

'55 W120 180, '08 W211 E350 Sportline
+ some 914's