I would suggest you not drive the car since the gas is or must be varnish already. Well if the car does start and can be driven, just drive the car for a bit but then you must change the fuel filters and accumulators. Then give the car a full tune up and drop the tank to clean it out. This is what I would do If I was in your position.

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2001 E55

2001 E320 Sedan

2001 Subaru Legacy

2006 SLK280

2016 Subaru Outback 3.6