General description of the programmable injection system 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...
Electronic control unit (ECU) To supply fuel to the cylinders at the right time and in the right amount, the control system must perform various functions. The ECU is the heart of the programmable fuel injection system (PGM-Fl). It uses a...
Sensors and inputs Crankshaft, TDC and CYL sensors crankshaft angle sensor signal (CRANK) used to determine injection timing and ignition timing, and to determine engine speed. The sensor's TDC signal is used to determine the ignition...
ECU Controlled Outputs The main purpose of the ECU is to maintain a good level of performance in any situation. The ECU interprets and compares the various input signals from the sensors and uses the resulting calculations to control the...
Fuel system Fuel pump The fuel pump is installed inside the fuel tank, thus saving space and simplifying the fuel line system. The fuel pump consists of a DC motor, a centrifugal pump, a safety valve to protect the fuel line...
Maintenance Precautions Do not operate the fuel pump when the fuel lines are empty. Do not operate the fuel pump when it is removed from the fuel tank. Do not use used clamps on fuel supply hoses. Washer (s) below any fuel system bolt...
Fault codes When damage is noticed, the ECU stores the identification code and turns on the indicator light "CHECK ENGINE" (engine check). The code will remain in memory until it is erased; The warning light on the instrument panel...
Fuel pump — testing 1. The easiest fuel pump test is to listen to it. The noise of the running pump should be heard 2 seconds after the ignition key is turned to the position "ON". The noise is easier to hear with the fuel filler cap...
Fuel Injector — Electrical Check 1. Turn the ignition key to position "OFF". 2. Disconnect the wiring harness from each injector (nozzles). 3. Measure the resistance between the two injector clamps. The correct resistance for everyone is 1.5-2.5 ohms....
Injector resistor — check 1. With the ignition off (in position "OFF"), disconnect the harness connector from the resistor. 2. Measure the resistance between terminal A of the resistor connector and the other terminal of the connector. When...
Main Relay — Test 1. The simplest test for the main relay is that the engine starts and runs. If so, then the main relay is functioning correctly. 2. If it is necessary to check the relay, remove it from under the dashboard and...
Check engine indicator Lamp health "CHECK ENGINE" The dashboard checks the ECU each time the ignition key is turned to "ON". The lamp should burn for 2 seconds and then go out. Under normal circumstances, the lamp does not remain lit when the...