i turned my car on and got a check engine light and i ran the code it's 023 m/c solenoid, how can i fix this?

Meter the resistance of the MC solenoid. It is easily accessible on the top of the carburetor (the blue connector):

http://mysite.verizon.net/strey/files/E4METopView.jpg

Expect to measure about 20-35 ohms.

Make sure the electrical connector is secured. A poor connection or open circuit can also set that error code.

To add to what Blue Bowtie said above, the clip that holds the harness onto the connector likes to get brittle and break off. This can cause the harness to wiggle out just enough to not make contact, but still "look" like it's connected.