Cleaning fuel injectors is a service frequently recommended by dealers and repair shops, but unless there are noticeable signs of clogged injectors (such as a rough idle, stalling, poor acceleration or high emissions levels) it might not be necessary. One tipoff is that fuel injector cleaning is not typically listed on automakers’ routine maintenance schedules.
Many shops promote a quick/easy injector service that runs a cleaning solution through the injectors while they’re still mounted in the engine. A more thorough (and expensive) process for severely clogged injectors requires removing the injectors and cleaning them on a machine designed for that purpose.
Fuel injectors clog when deposits build up over time and thousands of miles; when that happens, they don’t deliver the fine mist of gas that provides maximum performance and efficiency. If that happens, you’ll notice a loss of engine performance or lower fuel economy.
The type of gasoline you use also can be a factor. All gasoline is required to contain detergents that prevent carbon deposits, varnish and other gunk from forming in the fuel system, but not all brands use the same amount. Lower-priced brands often use only the minimum, but the so-called Top Tier brands use more detergents, and some vehicle manufacturers recommend them because of that.
Detergents have been required by the EPA since 1995 because many vehicle owners complained of clogged injectors and fuel-system deposits. Not only has gasoline gotten better since then, but so have the injectors, so problems aren’t as widespread as they used to be.
However, gasoline direct injection, a more sophisticated injection system that operates under higher pressure, is becoming commonplace in engines, and some GDI systems have proved to be more prone to clogging than regular fuel injection.
That’s why some manufacturers, such as Hyundai and Kia, among others, recommend adding a fuel system cleaner to your gas tank periodically if you’re not using Top Tier gas on a regular basis.
Many other gasoline additives that are supposed to clean fuel system parts are also available over the counter, and they may help keep things clean enough so that fuel injector cleaning isn’t necessary. The additional detergents found in Top Tier gas should do the same thing, which might be all your fuel system needs.