1994 Infiniti Q45 BaseFACTORY OEM SERVICE PROCEDURE

Fuel Control: Notes

ECM controls fuel system based upon sensor input signals. See FUEL CONTROL SYSTEM INPUT SIGNALS table. If feedback system does not function properly, check input signals before replacing ECM.

FUEL CONTROL SYSTEM INPUT SIGNALS

Application Model Usage
A/C Clutch Signal (1) Q45
Battery Voltage Q45
Closed Throttle Position Switch Q45
Crankshaft Position Sensor Q45
EGR Temperature Sensor (2) Q45
Engine (Coolant) Temperature Q45
Heated Oxygen Sensor (3) Q45
Ignition (START) Signal Q45
Mass Airflow Sensor Q45
Park/Neutral (Inhibitor) Switch (5) Q45
Power Steering Pressure Switch Q45
Secondary Throttle Sensor (6) Q45
Sub-Crankshaft Position Sensor Q45
Throttle Position Sensor Q45
Vehicle Speed Sensor (4) Q45
(1) Signal received from automatic A/C amplifier.
(2) California models only.
(3) 2 used.
(4) Signal received from transmission control unit.
(5) Signal received from P/N relay.
(6) Traction control system equipped models.
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.