Pentagon officials, frustrated at the failure of a new long-range Air Force missile in its last five flight tests, have delayed production of the weapon for at least two years and threatened to scrap the $1.4-billion program, sources said. The abysmal performance of the AGM-130 missile has set back the Air Force's plans to arm fighter planes with a weapon that would allow pilots to fire at ground targets from a safer distance. Air Force spokesman Lt. Col. Jim Phillips said in a recent interview that in several realistic "live-fire" tests over the last 15 months, the missile was fired from a plane and swerved out of control. In some earlier ground tests, the rocket motor that is attached to the missile exploded, he said. Phillips traced the problems of the $250,000 missile, under development by Rockwell International Corp., to quality control problems at the company's Duluth, Ga., plant. Production of the 13-foot, 1 1/2-ton missiles, originally scheduled for late 1986, has been moved back at least until the end of 1988, Phillips said.