The "check engine" light on my '96 Camry (107,000 miles) just started coming on after I fill up. I took it in and the computer didn't find anything wrong. I'd already checked the gas cap. It's also running rough and has lost 5 mpg. It has a new air filter and fuel filter. It's been a great car until now with a minimum of problems. Any ideas?

Same thing on mine.... 96 2.2L 130k miles. Check engine light came on. I did use 87 octane last fill up with fuel cleaner.

Do these lights every go off by themself?

One possibility is that you have a plugged injector. You can clean them yourself or have them cleaned. Adding an additive to the gas will not help if the injector is totally plugged.

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