engine light on

Have it scanned for codes.

it could just be for something minor like an emissions failure. my 97 es300 has a code for a stuck open exhaust gas recirculation valve.

Had the same problem. A mechanical associate of mine said "take it on the highway and drive hard for a few minutes like you are trying to get away from a chasing cop. It might fix the sensor problem. I did as he suggested for about three minutes, and the light went out and no problem since. He said to run the car hard and fast for a couple of minutes every few weeks. It's a good and cheap possible solution to clear the fuel sensor that might be causing the problem. Cheers and good luck.

Take the battery off for 5 minutes, then hook it back on and drive streets and freeway, it will take about 15/20 miles for the computer to go thru the system,sometimes it gets stuck . It could also be vacume hose?

Usually if the gas cap is loose sometimes just tighten it and drive about 2 miles and the light should go off.