So I recently got my Honda Civic from my brother and the check engine lights been on since he had it. He gave it to me because he now has a new car and I went to a shop to fix up everything that was wrong with it, wheel barrel, axle, and other problems. They even checked for codes that could cause my check engine light to turn on and apparently there were none so they erased the check engine light for me and said if it turned on I shouldn't worry about it. A few weeks after I finally went on the freeway for the first time to pick up my niece and on the way back it turned on. Should I be worried?