Accord and Prelude models 1990-91
Programmable fuel injection system (PGM-FI) - a fully electronic engine control system based on a microprocessor. Electronic control unit (ECU) responsible for:
- determination of the time and duration of fuel injection,
- air intake control,
- setting the ignition timing,
- mixture enrichment at cold start,
- fuel pump control,
- fuel cut-off
- operation of the air conditioning compressor,
- generator control,
- operation of the EGR system,
- cleaning cycles.
The ECU receives electrical signals from a large number of sensors and sources located both on the engine itself and around it. The output signals from the ECU are determined by processing the incoming signals in accordance with the programmed parameters. The ECU contains additional memory, redundant and fail-safe functions, and diagnostic capabilities based on symptomatic diagnosis and memory of error codes. For verification, always use the diagnostic cards as well as the Honda test harness, voltmeter and ohmmeter.