Engine light is on, oh no!

My girlfriend who now drives my 2001 aurora more than I do tells me the engine light is on. Couldn't seem to find what was wrong. My mechanic hooked it up to a computer and found that one of my secondary valve air injection shut off valve vacuum control solonoid was leaking. I had it replaced. It cost $338.50 Canadian, not including the $45 computer check and then tax for a bill of $490.81.

Has anyone had this problem?

Thanks.