No idea if this helps but I had a strange issue with my 95 E300D, its high speed fans would switch on when started from cold and then go out with an intermittent on off dance at approximately 60C on the gauge. Every single time.

It also caused the A/C to cut out.

The high speed fans are controlled by the push button unit - there was a compound problem of wrong wires in the connector pins and one slightly corroded wire in the main grounding point in the cabin.

For your car I have a thought, when the MAF is disconnected the fans kick on high speed in other similar vintage MB and the car is stuck in limp mode. Your fan going high speed may not be a cause but a "result"

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)