60,000 mile maintanance

[rbme1]

My mint condition 2002 4 cyl Solara just passed 60,000 miles. One dealer told me to change the plugs another one said not until 120,000. I replaced the battery and a little while ltr the engine light went on. The car runs flawlessly except I notice what seems to be a slightly high idleing of the engine. Assuming it just needs the maintanance what should definitely be done and what is optional? I appreciate any assistance.

Thank you

[dug320]

Seafoam and the idle will return to normal.