As Honda's warranty booklet states, the powertrain warranty covers the engine's "cylinder block and head and all internal parts, timing gears and gaskets, timing chain/belt and cover, flywheel, valve covers, oil pan, oil pump, intake and exhaust manifolds, engine mounts, engine/powertrain control module, water pump, fuel pump, seals and gaskets." There's no mention of fuel injectors in the powertrain warranty.
The fuel injectors are external parts and covered under the new vehicle limited warranty for 3 years or 36,000 miles except in California, Connecticut, Delaware, Maine, Maryland, Massachusetts, New Jersey, New York, Oregon, Pennsylvania, Rhode Island, Vermont, or Washington where they are covered for 7 years or 70,000 miles. The fuel injectors are also covered by the Honda Care extended warranty and by some third-party warranties.