Euro 5 Conversion

Whom better to ask than Mercedes-Benz?

Have you tried any fuel additives? Are you asking is it legal? Do you know exactly what the problem is with the diesel you are using?

http://www.bellperformance.com/blog/bid/110843/Diesel-Fuel-Additives-Top-5-Things-You-Never-Knew-You-Didn-t-Know

Sprinter....

I'm sure it can be done. I'm not sure if it is legal to do this. There might even be a simple, legal modification to your Euro 5 compliant engine/fuel system that can handle your local blend of fuel. Contact your local Mercedes dealership or approved mechanic.

Depends on what they changed on the vehicle's engine to meet the euro 5 standards.

https://www.theaa.com/motoring_advice/fuels-and-environment/euro-emissions-standards.html

If it's just a matter of tearing the guts out of a particulate filter and bypassing a few other mechanical emissions devices like an EGR valve and makeing the engine think they are still working by modifying sensor signals then yes it could be done (legal or otherwise) without too much work providing you are mechanically inclined and a bit clever.

But if they went with a whole different engine and fuel system design like being all electronic drive by wire Vs the old all or near all mechanical injection then no it's not likely you could do a fuel and emissions design rollback yourself and you would be time and money ahead to go and find a older vehicle.

This will run just fine on just about anything including salad oil.