chekc engine light came on the other day and then went off after about 15 minutes. it came back on today and im taking it to my friend who is a mechanic tomorrow but are there any major things i should look for while this light is on??
thanks

 

this is a pretty generic post, you might need to include some more info. Has the vehicle been acting strange in any way, getting worse mileage, less power, noises, et.?

what is the engine, the year, and the mileage? any recent service or damage?

 

1999 sr5 4runner with 150,000 miles. hasn't acted strange in any way, no damage and the light just comes on for about an hour and then later it won't be back on.

still haven't taken it to my friends

 

It could be anything... Maybe O2 sensor, EGR valve, something like that. Go to autozone or somewhere like that and have them pull the codes. Then come back and you can get an answer.