my ka keeps tryin to turn off while im driving

[ddf2006]

the car turns on fine and wen i start driving it fine for a lil while, once i get down the street and push the clutch and start slowing down, the idle immediatly goes down to around 300 and gets ready to shut off on me. i raised the idle so it dont turn off as often but it still gets real low and turns off only sometimes but always goes real low. please let me kno if u have any suggestions to wat might be wrong. thank you.