The latest 9 percent OPEC oil price increase will cost American consumers about $4.3 billion a year and add about 0.3 percent or 0.4 percent to the inflation rate.

The new $14.54-per-barrel price will mean more than a 4-cent-a-gallon increase in gasoline prices at the pump, and similar jumps in the cost of other petroleum products.

Even though all OPEC did-except for any "surcharges" some countries may add later-was to advance increases already set to take place by Oct. 1, the action is another threat to President Carter's beleaguered anti-inflation program.

"It can only complicate our prospects of trying to bring inflation in our economy under control," said Alfred Kahn, chairman of Carter's Council on Wage and Price Stability.

In a plea directed at both business and labor, Kahn added, "We must recognize, however, that it makes little sense to try and raise our wages and prices to recover this loss. To do so is to pass on the cost to others."

Compared to what OPEC had already planned, conusmers will be paying only about $1.1 billion extra in the U.S. And about $300 million that will go to U.S. oil producers whose output-about 35 percent of all domestic production-is free from price controls.

But beyond the higher floor for oil prices, administration officeials were uncertain what the real outcome of the meeting in Geneva will turn out to be. The OPEC communique said member nations were authorized to add a surcharge of up to $4 a barrel if they wished. There were also reports that some nations may reduce their oil production.

"It's exactly what you would expect in a chaotic situation-chaotic," one administration energy expert declared. "We just don't know exactly what happened yet."

The permission to sue surcharges was "a shrewd move on OPEC's part," according to one Washington energy economist. "The higher price provides a floor and the surcharge gives everyone a hunting license."

Whether the market will alow some countries to impose a surcharge is another matter.

Saudi Arabia's oil minister, Sheik Ahmed Zaki Yamani, said his country will not impose a surcharge. However, a Kuwaiti official said his country would continue the $1.20-a-barrel surcharge it has been charging. And Algeria announced that it would go for the full $4 a barrel.

Yamani also said that Saudi oil production, which has been running more than 9.5 million barrels a day in the wake of the big drop in Iranian oil exports, would be reduced to 8.5 million barrels when Iran's exports reached 3.5 million barrels. Iran now is exporting about 2.5 million barrels a day.

If Kuwait continues the $1.20 surcharge, and neighboring Saudi Arabia has none, industry experts think that Kuwait sales, and their production, will drop from its current level of about 2.2 million barrels a day.

In the view of administration energy officials, current Iranian exports have just about put world supply and demand back into balance, given the need to rebuild worldwide inventories by about 100 million barrels. They estimate supplies were drawn down by that amount or more during the weeks Iranian exports were stopped.

Inflation fighter Kahn said the OPEC increase also "accentuates how essential an energy policy is to bringing this country as far and as fast as possible along the road to diminished dependence on foreign oil supplies. This means doing everything we can to encourage additional domestic production of oil and gas, and of other energy sources, and practicing as much conservation as possible."

Menawhile, President Carter has postponed for about a week making decisions on a series of actions to deal with the Iranian shortage, possibly including decontrol of domestic crude oil prices.

Presidential press secretary Jody Powell said that Carter "indicated less than complete satisfaction" with the energy proposals that had been submitted to him and had asked that they be revised.

The 9 percent OPEC increase came on the heels of a 5 percent increase effective Jan. 1 that had raised the world price to $13.34. Even the dull jump from last fall's $12.70 price to $14.54, effective next week, is only a drop in the bucket compared to the increases following the Arab oil embargo in 1973.

In today's dollars, oil prices than went up by $11.85 a barrel, instead of the $1.84 of the last three months.

However, some statements by oil mininster attending the OPEC meeting implied that other increases could come later this year. The next OPEC meeting is set for June.