I don't have a scangauge and can't afford one right now so I thought maybe posting here would help. Last year my check engine light came on a couple of times at the end of the summer but it went away and I can't remember how. Today was the warmest day of the year so far for us and my check engine light came on again. It seems to happens when it's warm, I'm accelerating and I think the A/C is on but I can't be 100% sure about that. I popped open the hood and looked around but I didn't see any issues. All of my fluids were at the correct level and my engine wasn't hotter than it should be. I believe there is a 2 MPG drop but I've only been through 1/2 of the tank so I'm not sure about that. Without having a scangauge, are there any other cheap alternatives to finding out what code is logged? I've heard that Toyota charges something like $80 to find out. Any other ideas that could help me?