Mitsubishi Repair: engine code po1490, emmission controls, eclipse gs

Question
I have a 96 eclipse gs, the check engine light was on so I took it to auto zone to seewhat the problem was it pulled a code po1490 somthing about emmission controls, they tried to look the code up in the conputer and could not find any thing about it. when the check engine light was on the car ran fine but now it is off and after the car is warmed up and you shutt it off for a few min. it dose not want to stay idleing untill it runs for a couple min. pleas help

Answer
Jeremy,
Typically when the check engine light (CEL) comes on due to an emissions problem, the light will stay on indefinitely until the car's computer (ECU) is reset.  For your CEL to turn off on its own, may indicate something else.  Sometimes the universal scan tools that Auto Zone uses makes a 'best guess' to what a code is since all car manufacturers make codes that only their proprietary scan tools can read.  But Auto Zone is great first place to go when your CEL comes on.  

Go to this page for a great reference for your car:http://www.2gnt.com/nuke/modules.php?name=Sections&op=viewarticle&artid=8

Not only will this page tell you exactly what the codes mean, but it gives you an instruction on how to find out the actual codes yourself at home.  Try the procedure listed on this page next time you CEL comes on, and you'll find exactly what the cause is.
Good luck!