My question involves vehicle registration or title in the state of: California

Last Saturday I purchased a Vehicle, at the time of the purchased he showed me the smog paper from last year and guaranteed that it will pass smog. After paying for it in full we took the truck. When we brought it in for a smog test it failed.

I just called the seller explaining to him the situation and he gave me a hard time and started swearing etc.. etc..

Since we purchased the vehicle we've put less than 100 miles on it and that's basically to drive from the seller home.

What are my options at this point?

BTW: There was no bill of sales or anything, he just handed me the title and call it it.