Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1993 Acura Legend Base, AutomaticFACTORY OEM SERVICE PROCEDURE
Map Sensor
- MAP sensor is located inside control box on firewall. Unplug connector from MAP sensor. Turn ignition on. Measure voltage between Yellow/White and Green/White wires. If voltmeter does not indicate about 5 volts, repair wiring between MAP sensor and ECM. If wiring is okay, replace ECM. If voltmeter indicates about 5 volts, go to next step.
- Turn ignition off. Connect test harness between ECM and vehicle wire harness. Turn ignition on. Measure voltage between terminals D17 and D21. If voltage is not as specified in MAP SENSOR VOLTAGE table, check sensor output wire between MAP sensor and ECM. Wire is Yellow/White. If wire is okay, replace MAP sensor.
MAP SENSOR VOLTAGE
| Vacuum Applied - In. Hg | Volts |
|---|---|
| 0 | 2.8-3.0 |
| 5 | 2.3-2.5 |
| 10 | 1.8-2.0 |
| 15 | 1.3-1.5 |
| 20 | .8-1.0 |
| 25 | .3-.5 |
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.