Pontiac Problems? Ask a Mechanic for Answers ASAP
Is your fuel gauge working correctly, these sometimes had a problem with the level sensor and a line in the tank interfering which threw this code.
then there is likely a leak somewhere else in the system, most of it will require smoke charging the system to isolate but you can check the purge valve so lets start there. Number 6 in this picture is the purge valve disconnect the electrical connector and the hose going to it then start the engine and see if vacuum is being pulled through the valve by putting your finger over the opening. If it is then it needs to be replaced.