Energy futures resumed last week's rally in early trading Monday, but ran out of strength and closed in a slump.
Gasoline prices settled higher, but surrendered most of the sharp gains posted earlier on the New York Mercantile Exchange. Crude and heating oil closed mostly lower.
The June contract for leaded gasoline surged ahead by 1.86 cents a gallon before going into a tailspin and settling only 0.04 cent higher.
Tight gasoline supplies and growing demand have given energy futures a substantial boost in the last week, but the market remains uneasy and subject to abrupt reversals, said Peter Beutel, an analyst in New York with Rudolf Wolff Energy.
On the one hand, he said, the market may have dropped too low during its recent collapse and it won't take much to bring it back up.
On the other hand, Beutel said, "there are still plenty of bearish fundamentals around" that can sink the market at any time.
During Monday's rally, crude oil for delivery in June advanced as high as $13.95 a barrel, but then turned around when it was unable to break through the $14 barrier, analysts said.