For the 1,000 voters of this village set in the pine forests above the central city of Coimbra, three main issues are at stake in Sunday's parliamentary election: running water, sanitation and a school to replace the factory warehouse where their children are taught.

In the 10 previous national election campaigns since leftist Army captains ended a half century of dictatorship in the 1974 Revolution of the Carnations, caravans of politicians have threaded through the dirt streets here making pledges of modernization that were never fulfilled. This time they were met with barricades.

The barricades expressed the frustration of a rural population whose hopes that democracy would lift the interior of Europe's poorest country out of its backwardness have been dashed by repeated government upheavals.

"The revolution gave us the freedom to speak up for what we want," said villager Carlos Cortez, "but it hasn't got us very far. Financially, we're worse off than before."

"We don't care what party they belong to, we're keeping all the politicians and campaigners out," said Jose Pereira, 35, whose cement block factory closed this year amid a harsh economic recession. "We've been promised everything over and over again, but the truth is the revolution hasn't reached us here."

Three months before Portugal joins the European Community -- an event that outwardly reflects prestige and progress toward industrialized status -- Espirito Santo das Touregas, like similar villages across the country, feels it has been abandoned to Third World poverty.

Patience wore thin one night in the midst of the current campaign when chapel bells summoned the villagers to discuss their plight. By morning, oil drums and lumber barred entry to the electioneering politicians of all persuasions.

Despite progress in some areas of the economy, the real earnings of Portuguese farm workers dropped by a quarter in the past five years, unemployment is rising above 11 percent, bankrupt companies owe workers millions of dollars in unpaid wages, and Communist labor unions say the urban poor suffer widespread malnutrition.

This recession partly resulted from a tough austerity drive imposed by Prime Minister Mario Soares, the Socialist Party leader, when he returned to power in June 1983. The program succeeded spectacularly in bailing Portugal out of a balance-of-payments crisis caused by the overspending of previous governments. But Socialist leaders now admit they may have underestimated the impact and duration of austerity on the domestic economy.

"We have suffered for each reduction in the foreign debt," said Cortez, a factory worker. "Everything has gone up sharply except our wages."

As Portugal began to turn the corner this year with inflation expected to fall from 30 to 19 percent, purchasing power stabilizing and forecasts of industrial expansion, a government collapse pitched the country back into political turmoil.

Recurring elections are the main symptom of the instability that has disrupted Portugal's emerging democracy and stunted economic growth. Sunday's vote was provoked two years ahead of schedule by the breakup of the ruling coalition of Socialists and Social Democrats in a dispute over economic policy. Similar quarrels have led to the collapse of 15 governments in the past decade.

The crisis has pitted the two former coalition partners against each other as major rivals in the voting for 250 parliamentary seats. The smaller Social Democratic Party is led by Anibal Cavaco Silva, an aggressive politician who took over the divided party in May.

"I have polarized the country and confronted the people with a clear choice between the Socialists and us," he said this week.

It is a choice they have made before. The same coalition of Social Democrats and Christian Democrats that Cavaco Silva is advocating now ruled from 1979 to 1983 before it collapsed amid factional infighting. Cavaco Silva said the right-wing alliance lost its way after former leader Francisco sa Carneiro was killed in a December 1980 air crash. He now apparently intends to emulate the late premier's abrasive leadership. In the last election the Social Democrats won 27 percent of the vote and the Christian Democrats 13 percent.

In an attempt to break the pattern of ill-fated coalitions, the Socialists are campaigning for a sufficient majority to govern alone, seeking a 7 percent increase in their vote to 43 percent of the total. Soares is stepping down from the premiership to run for the presidency in an election scheduled for January, conceding his place to Antonio Almeida Santos, an astute and experienced lawyer who lacks Soares' crowd-rousing flare.

While the pro-Soviet Communist Party dominates the southern land reform zone and conservative voters hold sway in the strongly Catholic north, the Socialist heartland is in moderate, middle-of-the-road communities such as Espirito Santo das Touregas, where they took more than half the vote in 1983. But the mood of villagers here today indicates that the country's largest party and senior governing partner may have to bear the brunt of dissatisfaction with falling living standards.

Possibly more upsetting to the Socialists is the unexpectedly strong momentum gathering behind a party founded little more than three months ago. The Democratic Renewal Party is running on a ticket of a "new morality" for Portuguese politics, fighting corruption and incompetence. But its real strength comes from the prestige and popularity of its central figure, President Antonio Ramalho Eanes.

Eanes, maintaining his reputation for integrity, is refraining from leading the party until January when he steps down from his second five-year term as head of state. His wife, Manuela Eanes, who is representing the president in the campaign, expresses confidence that the party will grow from an expected 10 to 15 percent of the vote in this election to an overall majority when her husband is at the helm.

Political analysts here forecast the eanista party could soon emerge as a major new force in Portugal's tangled politics. But for the villagers of Espirito Santo das Touregas it still has a lot to prove before it will be welcomed inside the barricades.