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.
1990 Geo Metro L3-61 1.0LFACTORY OEM SERVICE PROCEDURE
Engine Control Module: Locations
ECM Wiring Location:
1 = RADIATOR COOLING FAN MOTOR SWITCH
2 = COOLANT TEMPERATURE GAUGE SENSING UNIT
3 = EXHAUST GAS RECIRCULATION VACUUM SWITCHING VALVE
4 = AIR TEMPERATURE SENSOR
5 = COOLANT TEMPERATURE SENSOR
6 = THROTTLE POSITION SWITCH (M/T ONLY), THROTTLE POSITION SENSOR (A/T ONLY)
7 = FUEL INJECTOR
8 = MANIFOLD ABSOLUTE PRESSURE SENSOR CONNECTOR
9 = GENERATOR CONNECTIONS
10 = STARTER MOTOR CONNECTION
11 = GROUND CONNECTION
12 = IDLE SPEED CONTROL SOLENOID VALVE
13 = BATTERY POSITIVE TERMINAL
14 = ENGINE WIRING HARNESS
15 = DISTRIBUTOR WIRING
16 = OXYGEN SENSOR CONNECTOR
17 = OIL PRESSURE SWITCH CONNECTOR
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.