Problem
The clogging of the injectors leads to a poor quality of fuel atomization, resulting in an irregular flow to the engine. This problem is particularly marked in GDI engines since, unlike PFI systems, in this configuration the injectors are located directly in the combustion chamber. Working in high temperature conditions, in close contact with burnt gases, they are therefore more subject to the accumulation of carbon residues which compromise their regular operation. Deposits can also cause the valves to stick, thus altering the correct fuel/air ratio and therefore the combustion efficiency.
When the fuel system gets dirty, not only does the engine performance decrease in terms of driveability and response, but there is also higher fuel consumption and particulate emissions.