Indeed, the engine light can mean a number of things. However, it seems a very common problem with Ford is the EGR system and it can make your engine light come on. The EGR system has become very complicated. Besides the ERG valve itself, there is a differential pressure monitor that decides if enough air is flowing through the valve. There are also solenoids for opening and closing the valve. What all this is intended to do is to monitor the health of the EGR system and it can be a pain in the ass. The best way I know to keep this from happening is to use a good fuel injector cleaner regularly. I can recommend Red Line. For about $5 a bottle you can treat 100 gallons of gas. Using synthetic oil can help too. Keeping the formation of petroleum based combustion by products down to a minimum is the idea behind using these products. As for reading the codes, get a code reader and do your own testing. OBDII testers are supposed to work on most cars nowadays, so it would be a good investment. If you do test your own car, remember to warm the car up first. After warming do both the key on, engine off test and the key on, engine on test. Two different tests! Record the codes, if any, and look up the codes in the tables. Testers usually come with code look up tables. Hope this helps.
