Intrmittent stalling. on 2000 Hyundai Elantra

Runs great then for no apparent reason the engine slows and even shuts off. Fuel filter or Fuel pump?

Do you have any warning lights illuminated? If yes, have the computer scanned for trouble codes.

If no warning lights, it is very possible you have a fuel issue because fuel pump problems rarely (usually never) set the check engine light. It is still a good idea to have it diagnosed.

Here's an article that may help isolate the conditions under which your stalling occurs. If the diagnosing technician can duplicate the problem, there is a greater chance of solving the problem. hope this helps!