[Saudade]

You can find cheap scanners on eBay. The cheaper ones (less than $50), give you the codes but you have to look them up in a book. Mkae sure you get the right one for your manufacturer. The more expensive ones can tell you the problem on screen. Even better ones can allow you to run real times diagniostics, get Dyno data, even graph results.

I opted for the cheap one.