The sale of F16 fighter-bombers has grown here into a major test of the Reagan administration's commitment to Pakistan in the same way hat the sale of AWACS radar planes took on special significance for Saudi Arabia, according to a wide spectrum of Pakistani and diplomatic sources.

"In this region, the F16s are as much a symbol as the AWACS were in the Middle East," said a well-informed Western diplomat.

If Congress does not approve the sale, diplomatic sources and Pakistani officials are certain that the newly rejuvenated strategic link between the United States and Pakistan will fall apart, almost before it takes root.

The $3.2 billion economic aid and military sales package, along with a separate $1.1 billion sale of 40 F16s, have been approved by the Senate and await a vote in the House, where there is some opposition to the fighter sale.

The Reagan administration has made Pakistan the eastern anchor of what Secretary of State Alexander M. Haig Jr. has called "a strategic consensus" to confront the Soviet Union. The swath stretches in an arc from Pakistan through the oil-rich Arab nations of the Persian Gulf, including Saudi Arabia, to Israel, Egypt and Turkey in the west.

Undersecretary of State James L. Buckley said in a New York speech last Tuesday, that Pakistan "stands as a barrier between Soviet ambition and the Indian Ocean approaches to the Persian Gulf."

Thus there is an expectation here that, if it prove necessary, Reagan and Haig will fight as hard for congressional approval of the F16 sale as they did for the AWACS, or Airborne Warning and Control System planes. Congress recently failed to reject a Reagan administration plan to sell five AWACS to Saudi Arabia.

Emphasizing the importance he attaches to the acquisition of the F16s, Pakistan's president, Gen. Mohammed Zia ul-Haq, refused in September to agree to the deal with the United States unless there was an accelerated delivery schedule for at least some.

The Reagan administration arranged to have six of the fighters delivered within 12 months, although due to a lack of ground support equipment, their use will be limited to six to eight hours' flight time a month.

Besides symbolizing their new relationship with Washington, Pakistanis see the F16 as a deterrent to what have become frequent violations of their airspace by Soviet jets from neighboring Afghanistan that cannot now be stopped by the antiquated planes of Pakistan's Air Force.

"I think it is going to be a very valuable deterrent," said Noor Ahmed Husam, director general of the Institute of Strategic Studies here, who has counted more than 300 violations of Pakistan's airspace, including a number of strafing attacks, since the Soviets invaded Afghanistan almost two years ago.

"What is more," he continued in an interview, "the F16 will be very important for the morale of the Air Force and the country. The planes will strike the fear of God into the Soviets and the Afghans.

"We don't want to use them for aggressive purposes, but every nation has the right of self-defense. The Soviets respect people who can hit back. Basically, they are bullies."

His views were echoed in interviews with highly placed Pakistani government officials who did not want their names used. "It will add new muscle to help us deter" the Soviets, one said.

Another explained that Islamabad's military planners understand that there is no way Pakistan can stand up to the full might of a superpower such as the Soviet Union, even with F16s and other American weapons.

He said, however, that getting the new arms means "we can make a larger aggressor pay a price in men and materials so it will think twice about attacking us."

Neither Pakistanis nor a wide variety of diplomats interviewed here buy the Indian argument that the acquisition of F16s will alter vastly the balance of power in the region in Pakistan's favor. India has the fourth-largest military force in the world and maintains its arms predominance over Pakistan with multibillion dollar military purchases. A deal with France for 150 advanced Mirage 2000 warplanes worth $2 billion reportedly is near completion, and a $1.63 billion deal with the Soviets was concluded last year.

Nonetheless, questions have been raised here about the wisdom of Islamabad spending so much money on one weapon system -- especially if Saudi Arabia fails to contribute expected funds for the purchase of the American fighter-bombers.

"They are crazy," one highly experienced diplomat here said. "More than half their money will be spent on 40 F16s. They could get so much more of all the other things they need if it wasn't for the symbolism of the F16."

Originally, Pakistan said the $1.1 billion cost of the two squadrons of 40 F16s would be borne by their Islamic friends -- widely believed to be Saudi Arabia. Now American officials such as Buckley acknowledge that at least some of the money will have to come from the U.S. military sales credits.

There are no signs here, however, that the Saudis have come through with any cash, according to well-informed diplomats, although the Pakistanis are believed to be working hard to nail the money down and there is an understanding that Saudi Arabia has pledged to come forward with $500 million when the funds actually are needed.

Even if Pakistan gets the Saudi money, however, it will take at least an equal amount from the $1.6 billion military sales credits in the American package to pay for the F16s. That will not leave much for other weapons Pakistan's military says it needs to replace outdated tanks and guns.

Nonetheless, according to all indications here, the Pakistani military appears firmly behind the F16 purchase.

But Husain, the head of the Institute for Strategic Studies, said, "It is the air that determines security on the ground. If you can keep the skies clean, a lot of things don't happen on the ground."