Dodge Repair: Check Engine Light, dry rack, warm weather

Question
 recently I have noticed that my check engine light kept flickering. I noted to that back during the winter it came on once and then went off by itself. It never started back up until last week when the warm weather arrived now it has remained on. Before I take it to a dealer I would like to know some of the reasons why the light would go on , if it can be reset and what I should be looking for to verify whether it is computer related or a catalytic computer problem.

Second question when turning right or left it sometime squeaks like it needs to be oiled what might this be

Answer
Hello scott
this could be a map senser it proulbly is the problem if bad cat you would smel a rotton egge smell weather will play with a mao senser if you want to reset the compuiter pull the neg cable for 5 min. And then hook it back up

On the front wnd it is hard yo say with out looking at it my self but it sounds like dry rack bushing.
have it checked by a shop.

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