You need to replace the manifold pressure sensor in most cases. The run from $20 to $100 and are fairly easy to replace.
Trouble code P0105 means: Manifold Absolute Pressure (MAP) Circuit Malfunction
your inake manifold is leaking or vancuun hose.
Trouble code P0662 means: Intake manifold tuning valve control circuit high (bank 1)
Code P0105 means:Manifold absolute pressure circuit malfunction
Code P0105 means:Manifold absolute pressure circuit malfunction
To send more pressure to the front wheels, where it is needed.
P0520 Code Engine Oil Pressure Sensor/Switch Circuit Malfunction
Engine oil pressure sensor circuit malfunction.
31manifold and/or airflow meter sensor signal circuit--airflow meter/circuit--manifold pressure sensor/circuit--ecu
Trouble code P0108 means: Manifold absolute pressure or barometric pressure circuit high input
If you mean PO660 it is Intake Manifold Tuning Valve circuit Malfunction. Click the link.
The trouble codes 23, 31, and 32 for a 1993 Geo Metro correspond to the following issues: Code 23: Intake air temperature sensor circuit high voltage Code 31: EGR system malfunction Code 32: Exhaust gas recirculation circuit malfunction