low ideling sometime causes car to stall

[stealthvirus]

1993 nissan 240sx stock engine olny cold air intakeQ- i have ben recently drifting in a open dirt lot so i can get the hang n feel of drifting which it has ben helpin me out but my main ? is since i ben doin that in a dirt lot i believe it did something to me engine now my car idel's between 1000rpm n gets lower to 100 n sometime stalls or seems like its goin to stall bc it drop 2 a very low rpm do u have ne suggestions on what may have happened to cause this

p.s if u can reply to my email address it would be greatly appreciated due to travelin i am not on here often like i usually am ty Sin Gregg B