low idle all of a sudden...help

When I let me car warm up the past two days...its idle has been really low at like 500(instead of like the usual,,, around 800). If i rev it to like 1000, it drops to like 400 and the lights kinda flash in the dash. One time they flashed all the "warning lights" blinked too. Its pretty cold here but isnt the engine sappose to idle higher to get warm when its colder? It actually stahled out once when i was backing up. Yea so is there anything i can check to see whats up with this change in idle?

Check your cold air idle control thingy its on the intake manafold. it might be messed up.

BISS screw, ISC motor, spark plug.... search around the forum for "idle problem" you'll come up with tons of similar problem and solutions.