Does Shell's "Nitrogen enriched" gas have positive effects? Shell gas stations here in Canada claim to be "nitrogen enriched"; * * * WHY SHOULD YOU USE SHELL NITROGEN ENRICHED GASOLINE? > It is the only gasoline that contains the patented and exclusive Shell Nitrogen Enriched Cleaning System > > Extensively tested for more than half-million miles in various engines and vehicles > > Actively cleans performance-robbing gunk from intake values and fuel injectors > > Acts like a protective barrier to shield fuel injectors and intake valves against future gunk build up > > Exceeds the stringent requirements of the world’s top automakers – Audi, BMW, General Motors, Honda, Toyota and Volkswagen – and is certified as a TOP TIER Detergent Gasoline > > No other gasoline protects better! * * * I looked around, but I couldn't really find any conclusive tests on wether it actually had a cleaning and performance-enhancing effect. Does it work as well as claimed?

A good starting point for information about this topic is The Gasoline Wars Chemical & Engineering News, vol. 87, pages 20-21.

First, when shell says "nitrogen-enriched", it does not mean that nitrogen itself (such as dinitrogen in air) is added to the gasoline. Instead, it means that an amine detergent compound is added to the gasoline.

Secondly, amine detergent compounds have been know for a long time to have cleaning effects. Various companies use specific amine compounds in their fuels.

There is a US patent 7901470 Gasoline Additives that is assigned to Shell and involves compounds of the form:

CH3(CH2)nNH2 where n is between 9 and 17, such as dodecylamine.

This patent includes test results concerning deposits in engines.