Hi all ~

My "check engine" light also came on last week. 1999 V70 with 32,000 miles. It came on during a very, very hot day. I hadn't gotten gasoline for four days prior so it didn't seem that it could be a loose gas cap. I did some online searching and called my local dealer as the car is still under factory warranty - both revealed the same information. Let the car run through 10-15 cycles of driving and see if the light goes off - a maximum of one week and a min of 4-5 days. The service guy reassured me that the car was not going to self-destruct nor leave me and the little ones stranded. Sure enough, four days later, no light on start-up!

Hope this helps.