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DFI Theory/Operation: Description: Notes

The Digital Fuel Injection (DFI) system combines engine control, fuel metering and emission monitoring into a computer controlled system. The Electronic Control Module (ECM) is the brain of the DFI system. The ECM is a digital electronic computer which receives and processes engine data, computes and interprets engine information, and sends instructions to various components. It provides fuel efficient operation with reduced exhaust emissions.

The Eldorado and Seville are also equipped with a Body Control Module (BCM) that is used to control various vehicle functions based upon data sensors and switch inputs. The ECM and BCM exchange information to maintain efficient operation of all vehicle functions. This transfer of information gives the BCM control over the ECM's self-diagnostic capabilities as well as its own.

CAUTION: Power should never be removed or applied to ECM or BCM with ignition switch turned to "ON" position. Before removing or connecting battery cables, fuses, or ECM/BCM connectors, always turn ignition switch to "OFF" position to prevent damage to modules.