Does shell nitrogen enriched gasoline actually clean ur engine?
Since I have started using the shell nitrogen fuel mileage increased 1 1/2 miles to the gallon.I am in Mississippi.I talk to one of the guys that goes around and checks the octane and accuracy of the pumps.He told me that shell does have the best burning gas.I will tell you that it took about 3 weeks to see the improvement in the mileage.Hope this helps.
