2001 Hyundai Elantra engine

My car was fine till 2 days ago when I drove it to work in a little bllisard! And all sudden the check engine light came on and the engine now has a rough idle shake the car back and forth and when I drive it its the same thing a jerking feeling! I put gas line aintifreeze in my tank thinking one the lines might frosen but that dident work and im wondering if I reset my computer if that work! Or if theres some thing simple I could do! Im a family man with not a lot of money and its my only car for work ans every thing lol ! And the last time I took it in they charged me 319$ just for looking at it and telling me what part to buy to fix it ! Well if u can help !
it be greatly apressated