Nozzle colors are typically consistent between stations that sell the same brand of fuel. However, even then there is no absolute guarantee because the type and age of the delivery pumps can vary. Older fuel pumps may reflect an earlier color scheme, or have had nozzle repairs in which a different colored part was installed. And, to debunk another belief held by some consumers, the shape of a fuel pump nozzle is also not an accurate indicator of the type fuel being dispensed.
A related issue is fuel pump nozzle filler pipes, which come in three sizes.
- Large-diameter filler pipes are usually found at truck stop diesel pumps where they are used to quickly fill the high-volume fuel tanks of over-the-road semis. A special adapter is required to use this size nozzle with most diesel passenger cars and light trucks.
- Medium-diameter filler pipes are used to deliver diesel at passenger car fuel stations. This size pipe helps prevent misfueling of most gasoline-powered vehicles because it is too large to fit through the unleaded fuel filler opening.
- Small-diameter filler pipes are used to deliver unleaded gasoline, but can also fit into the filler opening on many diesel vehicles. Some newer diesel models have an anti-misfueling device in the filler neck that prevents a smaller gasoline nozzle from being inserted.
So what can consumers do to prevent misfueling? Read the pump.
There are laws that require each type of fuel dispensed be clearly labeled. Rather than choosing based on nozzle color, a motorists should identify the pump labeling for the desired type and grade of fuel, then follow the associated hose to the correct nozzle, regardless of its color.
A few extra seconds when selecting fuel can prevent many hours and hundreds, or even thousands, of dollars in vehicle repairs.