Thanks for your responses guys.

I had been wondering what typical mileage these things got...it's really hard to find info on the net about them.

I'm going to take it into the shop and let them check it out really soon.

Do you think vapors escaping through the gas cap would be a major contributor to something like this? I know that a loose/missing cap in modern cars can trigger the "check engine" type of light, but I thought it was more because of pollution.

Cheers