cel on on 1999 Toyota Camry

my cel lite has been on steady for past 60k miles local Toyota dealer suggested change fuel cap, which I did, still on, can disconnect batty and lite goes off, but reappears after 30 miles of driving, any suggestions

by in Brighton, CO on April 12, 2009
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1 answer
ANSWER by , April 12, 2009
Your car has on board diagnostics 2 (OBD2). Did the dealer plug in a scan tool to a 16 pin diagnostic socket under the drivers side of the dash to retrieve codes stored in your cars computer. If they guessed it was a gas cap issue the light was turned on when the computer saw a fault with the evaporative emission system and the system needs to be properly diagnosed not just turn if the light. If it resets the Check engine light a second time there is a problem and a Toyota dealer or Toyota specialist/independent repair shop should be able to fix the problem.