2 REASONS FOR GASOLINE direct injection
Gasoline Direct Injection (GDI) is the latest fuel delivery technology that is now seen in more cars than ever. GDI has produced better performance, better fuel economy, and manufacturers are convinced it is efficient. GDI engines work by injecting fuel at high pressure directly into the combustion chamber, so higher voltages are used to provide quicker response than conventional fuel-injection systems. By spraying fuel directly into the engine cylinder, a cooler air-fuel mixture results, allowing the use of a higher compression ratio.
We received these 2006 Mazdaspeed 6 high flow injectors for a Gasoline Direct Injection application. Direct injectors are flow tested differently from the common rail injectors. Most injector cleaning companies cannot flow test direct injectors due to the lack of proper equipment. Common rail injectors are tested at 3 bar = 43.5 psi. Direct injectors are tested at 3 bar = 43.5 psi, 100 bar = 1,450 psi, and then at 200 bar = 2,900 psi. All injectors are cleaned in an ultrasonic tank to remove gunk, debris, and carbon build up. Then they are calibrated, and flow tested.
One example of GDI success is the Mazda's 3 SkyActiv engine that was developed in 2011. When Consumer Reports tested the new SkyActiv engine in 2014, the engine's fuel economy increased by 28 mpg to 32 mpg (15% increase). This is better mileage than you would get on other compact cars or subcompacts without spending more money for a hybrid or diesel. However, that added efficiency comes at a cost. Some owners have complained to Consumer Reports and the National Highway Traffic Safety Administration (NHTSA) that over time, direct injection can lead to clogged fuel systems and engine carbon buildup. The result can be engine hesitation and a loss of power. Some manufacturers have issued technical service bulletins (TSBs) to their dealers and recommend owners use brand name gasoline without ethanol additives or regularly add fuel-system cleaner.
It's important to note that not all cars with Gas Direct Injection will experience long term issues, but you want to keep up routine maintenance.
