I have a 2009 yaris engine light is on. What can be the cause?
Hundreds of reasons. Most common is loose, missing or un-sealed gas cap. Check your gas cap, make sure when you put it on it clicks once or twice. Even if that is it, the light will say on for a few miles. Otherwise you need an OBDII scan, many parts houses will do it free and give you code(s) that begin with P and 4 numbers. Example is P0300 is random misfire. Bring the codes back here, in a new question so we will see them, don't throw money at electrical parts that can't be returned. Some of the guys know what they are doing, others not so much
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