Hyundai Sonata: Engine Control System / Injector Description and Operation
The GDI injector is similar to a standard injector, but
sprays fuel at a much higher pressure directly into the combustion
chamber and has a swirl disc to get the fuel swirling as it exits the
nozzle. This aids in atomization of the fuel.
The ECM controls both the feed circuits (high side) to feed
voltage to the injectors and the ground circuits (low side) to energize
the injectors. Also, the feed for 2 injectors comes from the same driver
set. As the ignition coils are paired with cylinders (1-4 and 2-3), the
injectors are also set up in pairs.

Inspection
1.
Connect the GDS on the Data Link Connector (DLC).
2.
Turn the ignition switch ON.
3.
Measure the output voltage of the APS 1 and 2 at C.T and W.O.T.
Specification: Refer t ...
Specification
ItemSpecificationCoil Resistance (?)1.5 ± 0.075 [20°C(68°F)]
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