Cars, electronics and computers

This is the third time, in the year and a half that I've owned it, that the check-engine light on my Mazda Protege has come on... and, a little over a week later, gone off by itself. The first two times I took it into my mechanic, shelled out about a hundred and fifty bucks each visit, and was diagnosed with (a) the first time, a faulty EGR boost sensor (whatever that is... something in the emissions-control system), and (b) the second time, a faulty catalytic converter. Each time, the broken item would cost nearly a thousand bucks to replace. Was it an essential fix? "No," said the mechanic. Would the car get damaged if I didn't fix it? "No." Do I have to do it? (I like to make sure there aren't any loopholes.) "No, not unless you are due for an emissions check-up any time soon." The only downside to not replacing them was that, if something else went bad, I wouldn't know about it, because the check-engine light would have already been on.

"Don't worry about it," they said, "unless you notice a sudden change/drop in performance of the car -- misfiring, bad starts, poor fuel economy, that sort of thing. Then bring your car in." (Strangely, I've noticed a slight increase in my miles-per-gallon / miles-per-tank the past couple of weeks... Odd.)

So I didn't replace them. And, like I said, each time, a week later, the light went off by itself.

This time, I didn't go to the mechanic. Just gritted my teeth and gripped the wheel and puckered up my sphincter and positioned my left hand on the wheel to try and block out that incessant, glaring yellow light, and waited... and waited... and waited.

And this morning, it went off by itself. :)