With GDI, fuel is no longer sprayed on the intake valves, which eliminates the wash-over cleaning affect provided by the fuel. This results in a buildup of carbon deposits on the inlet side (top) of the intake valves and intake walls caused primarily by blowback from the crankcase ventilation system.
These carbon deposits create turbulence and restrict airflow into the cylinders causing performance and drivability problems (hesitation, stumbling, misfiring, even hard starting). The thicker the carbon deposit buildup on the valves, the worse the drivability problems.
Justice Brosthers GDI System Service eliminates carbon at 6 critical points: MAF Sensor, Throttle Body, Intake Valves, Injectors, Spark Plugs, Combustion Chamber. Our unique three-step process using professional fuel injection equipment thoroughly cleans the entire fuel injection system.