Fuel System - GDI High Pressure System Information
Group FUEL SYSTEMNumber 10-FL-019
Date DECEMBER, 2010
Model 2011 SONATA 2.4L / 2.0T
Subject
SPECIAL SERVICE INFORMATION AND SPECIFICATIONS FOR GDI HIGH PRESSURE FUEL SYSTEMS
DESCRIPTION:
In a gasoline direct injection (GDI) engine, highly pressurized gasoline is injected via a common rail fuel line and injectors that deliver fuel directly into the combustion chamber of each cylinder. In comparison, in a conventional multi-point fuel injection (MPI) engine, relatively low pressure gasoline is injected into the intake port of each cylinder. Due to high fuel pressures in a GDI system, servicing the GDI system requires special attention and handling procedures.
This bulletin provides special service information and specification for the GDI fuel system components. The following aspects of the GDI fuel system will be outlined:
A. Fuel Pressure Specification
B. High Pressure Fuel System Tightening Torque
C. SST For Tightening High Pressure Fuel Pipe Flare Nuts
D. High Pressure Fuel System Residual Pressure Warning
E. High Pressure Fuel Pump Installation
F. High Pressure Fuel Pipe Installation
G. Delivery Pipe and Injector Installation
APPLICABLE VEHICLES:
2011 and later Sonata vehicles equipped with the following engines:
^ 2.4L GDI engine
^ 2.0L Turbo GDI engine
SERVICE INFORMATION:
A. FUEL PRESSURE SPECIFICATION
^ The GDI high pressure fuel system operates at considerably higher fuel pressures than the conventional MPI fuel system.
B. HIGH PRESSURE FUEL SYSTEM TIGHTENING TORQUE
CAUTION:
When installing the high pressure fuel pump, fuel pipe, or the delivery pipe, be sure to follow the tightening torque specifications listed in the table below using a torque wrench. This is important since these are the main components of the high pressure fuel system.
^ Initially, hand-thread the fasteners fully without a tool. During this time, check the proper positioning of the fittings and components.
^ Afterwards, completely tighten to the specified torque using a torque wrench.
^ If the fasteners are not tightenened in a straight line with the mating bolt holes or fittings, fuel leaks may result due to broken fasteners or damaged threads.
C. SST FOR TIGHTENING HIGH PRESSURE FUEL PIPE FLARE NUTS
D. HIGH PRESSURE FUEL SYSTEM RESIDUAL PRESSURE WARNING
WARNING:
Whenever the high pressure fuel pump, fuel pipe, delivery pipe, or injector is removed after shutting off the engine, an injury may be caused by the release of highly pressurized fuel. Therefore, release the residual pressure in the high pressure fuel line by referring to the "Fuel System - Fuel Delivery System" section in the appropriate shop manual before removing the high pressure fuel system.
Summary of the Residual Fuel Pressure Release Procedure:
(1) Disconnect the battery negative cable.
(2) Remove the fuel pump relay.
(3) Reconnect the battery negative cable.
(4) Start the engine and then let it idle until the engine stops.
E. HIGH PRESSURE FUEL PUMP INSTALLATION
^ Before installing the high pressure fuel pump, be sure to place the roller tappet to the lowest position and position the fuel pump drive cam to the flat part of the lobe (as shown above) by rotating the crankshaft. If the roller tappet of the fuel pump is not placed in the lowest position during installation, the fuel pump may be positioned improperly, which may result in fuel pump piston damage, broken bolt threads, 0-ring tear, etc.
^ During a repair requiring fuel pump removal, cover the exposed fuel pump mounting hole in the adapter bracket to prevent any foreign substance or debris contamination.
^ Do not reuse the fuel pump mounting bolts. Once the fuel pump is removed, the removed bolts must be replaced with new ones.
^ When fastening the fuel pump mounting bolts, hand-thread the fasteners first, then gradually tighten 1/2 turn at a time to the specified torque while alternating between the two bolts in several cycles using a torque wrench. Failure to follow this procedure will cause misalignment to the assembly due to internal spring tension of the fuel pump and can result in damage to the adapter bracket.
^ Do not drop the fuel pump. External impacts may damage the internal components of the fuel pump. If this has occurred, confirm proper operation through performance tests prior to reuse.
^ Before installing the fuel pump into the adapter bracket, be sure to apply clean engine oil evenly over the entire surface of the 0-ring, roller tappet and fuel pump mounting hole. When installing the fuel pump, align the protrusion on the roller tappet to the groove in the fuel pump mounting hole.
F. HIGH PRESSURE FUEL PIPE INSTALLATION
^ Do not reuse the fuel pipe. Once the fuel pipe is removed, it must be replaced with a new one.
^ There are protective caps on both ends of the replacement fuel pipe to prevent foreign substances from flowing into the inside of the fuel pipe. Remove the caps prior to installing the fuel pipe to the fuel pump and the delivery pipe.
^ Refer to the "B. High Pressure Fuel System Tightening Torque" section in this TSB to properly install the high pressure fuel pipe.
G. DELIVERY PIPE AND INJECTOR INSTALLATION
^ Do not reuse the 4 delivery pipe mounting bolts. Once the delivery pipe is removed, the bolts must be replaced with new ones.
^ Do not reuse the injector retaining clip, 0-ring, backup ring, washer seal and combustion seal ring. Once an injector is removed, the 5 components must be replaced with new ones.
^ When installing the combustion seal ring into the injector, use the SST 09353-2B000 (shown above) and refer to the "Fuel System - Engine Control System - Injector" section in the appropriate shop manual.
^ When installing the washer seal into the injector, the rubber coated surface of the washer seal should come into contact with the injector body.
^ Before installing the injectors into the delivery pipe, be sure to apply clean engine oil evenly over the entire surface of the injector 0-ring. Be careful not to apply engine oil over the combustion seal ring.
^ Avoid dropping the fuel pipe (including the injectors) or bumping it into any hard objects since damage to the internal components may occur. If necessary, visually inspect and confirm proper operation with performance tests prior to reuse.
^ Before installing the injector into the injector hole in the cylinder head, clean the injector hole and avoid contaminants from depositing inside the injector hole. When inserting the injector, avoid bumping the injector tip into any of the surrounding components since the tip may become damaged from the impact.
^ When fastening the delivery pipe mounting bolts, first hand-tighten them fully and then tighten the 3 bolts in sequence (1-2-3 order as shown above) gradually in several cycles up to the specified torque.
^ Do not tighten the bolts completely all at once to prevent damage to the injectors. Fasten the bolts gradually in the above order. The delivery pipe should move less than 3 mm, whenever each bolt is tightened.
WARRANTY INFORMATION:
Normal warranty applies.