Fuel Injectors: Notes

Using a mechanic's stethoscope, listen to each injector for normal "clicking" operating noise at idle and under acceleration. To check secondary injectors, disconnect vacuum hose from boost sensor. Start engine and slowly increase speed. Using a mechanic's stethoscope, check that secondary injectors start clicking at 3500 RPM.
If clicking noise is not heard, check the crank angle sensor resistance. Using an ohmmeter, check between the terminals on the crank angle sensor connector. Resistance should be 110-210 ohms between terminals "G1" and "G2" or terminals "Ne1" and "Ne2". See Fig 1 .

Fig 1: Testing Crank Angle Sensor
Courtesy of MAZDA MOTORS CORP.
Check continuity of the wire from crank angle sensor to electronic control unit. If continuity is correct, check resistance of the solenoid resistor.
Using an ohmmeter, check resistance between terminals "FP" and "B" of the solenoid resistor. See Fig 4 . Resistance should be 5-7 ohms. If not, replace solenoid resistor.

Fig 2: Electronic Gasoline Injection System Components (RX7 Non-Turbo)
Courtesy of MAZDA MOTORS CORP.

Fig 3: Electronic Gasoline Injection System Components (RX7 Turbo)
Courtesy of MAZDA MOTORS CORP.

Fig 4: Testing Solenoid Resistor
Courtesy of MAZDA MOTORS CORP.
If solenoid resistor checks satisfactory, check EGI main fuse located forward of left strut tower. See Fig 5 . If okay, turn ignition on and ensure that main relay clicks each time key is turned on. Main relay is located behind left strut tower.

Fig 5: View of Main EGI Fuse
Courtesy of MAZDA MOTORS CORP.
If main relay does not click when key is turned on, check that battery voltage is present at main relay two pronged connector (Black/White) wire. See Fig 6 . If not, repair open in circuit.

Fig 6: View of Main EGI Relay
Courtesy of MAZDA MOTORS CORP.
If voltage is present at two pronged connector of the main relay, check continuity of main relay. Apply battery voltage and ground to the main relay side of the 2-pronged connector.
Using an ohmmeter, check that there is no continuity between terminals "A" and "B" or "C" and "D" when no voltage is applied. Check that there is continuity between terminals "A" and "B" or "C" and "D" when voltage is applied. See Fig 6 . If continuity reading is incorrect, replace main relay.