Can new fuel injected cars be converted to dual fuel with a preference to natural gas?
Yes. A dual fuel system incorporates a mixer in the air cleaner hose that is used when running on CNG (or LPG). When running on the alternate fuel, the fuel injectors are turned off. It is not as simple as installing a dual fuel system on older carbureted engines. In fuel injected systems, all functions of the engine are controlled by an ECU (Electronic Control Unit). The ECU monitors the oxygen level in the exhaust and controls fuel mixture, timing, throttle position sensing, and many other functions to keep emissions within allowable levels. When running on another fuel, an emulator must be used to keep the ECU functioning as if the vehicle were running on gasoline. The newer the vehicle, the more complex this is.
