Hi:
It sounds like there is a sensor problem that may be allowing too much raw fuel to be injected. Are you sure there is no leak? A rusty fuel line could be the problem or a hard to see fuel line under the hood. Check everything. If you have no luck, have the car's computer scanned for trouble codes. You can take it to most nationally recognized auto parts stores and they'll do it for free.
Let me know what you find.
Joe