Truck Repair: Check Engine Light On, oxygen sensor, scan tool

Question
Van,

I have a 2000 Ranger with 3.0 engine and 32,000 miles.  The check engine light has been on for a couple of weeks.  The manual states that the light indicates an emission control problem.  We do not have emission standards in Oregon.  Need I worry about the light?  What is the most likely reason it is on?  Thanks for you thoughts.  John

Answer
Hi John,
There is a whole chapter of things that can make the light come on. Some need sooner attention than others.
Check the owners manual, and I believe it will say a steady light suggests service is needed, and a blinking light indicates a more serious concern.
At any rate, it will need a scan tool connected to retrieve stored codes, which will give an idea of where to start looking.
It could be something as simple as someone driving it with the fuel cap off, which may clear itself.
Or it could be an engine related code that will need to be corrected and cleared.
Some parts houses will connect a scan tool and read the codes for you.
Just be aware that a code, such as oxygen sensor rich, doesn't mean to replace the oxygen sensor. It may be that the sensor is reading perfectly, in which case you need to find what causes the rich reading, which could be a fouled plug, dirty air filter, etc.
Good luck,
Van