Car savvy folks? Car question for ya!

Just wanted to add something:  If you run your car too much without paying attention to the check engine light and that sensor was indicating that your car was running too lean (too little fuel or too much air) you can destroy your catalytic converter.  (Too lean means the combustion is too hot and the exhaust is beyond the tolerances of the rare metals that they use in the catalytic converter.)

I'm not saying this is the case with your car, just that anytime anyone sees a "check engine" light come on, it's best to get it checked out.

I don't know about the Ford Escape, but the fuel pumps in some of the more recent vehicles have sensors as well. If you have a malfunctioning fuel pump, which could explain excessive fuel consumption AND running too rich/lean, that will trip the check engine light as well. My Grand Cherokee has a sensor for just about everything in the darn vehicle - I think the only thing it lacks is a sensor to tell me I've gained more than a couple of pounds (they could put that in the seat couldn't they?). My light came on in my 2000 Cherokee once and it didn't code on the diagnostic, so they disconnected my battery cables, then reconnected them and it never came back on. I'd certainly get it checked out though. I had a crank sensor go out in the middle of rush hour traffic, and my light had only been on for a day, so I tend to go in right away now.