The disruption accounts for part of the dent in Ford's sales, which also suffered from distribution bottlenecks affecting the replacement of its Fiesta and Kuga models.
Ford increased its 2013 European loss forecast in January to $2 billion from $1.5 billion and predicted global pre-tax profit in line with last year's $8 billion.
Sales incentives come in many forms and are difficult to track. By some measures, however, Ford's European discounts significantly outpaced competitors' last year.
Ford's average retail incentives jumped more than 30 percent to top 2,750 euros ($3,500) per vehicle in the region's top five markets, according to data from an independent market research firm seen by Reuters.
The Ford figure was more than 500 euros above the mass-market average, which rose by a more modest 11 percent in Germany, Britain, France, Italy and Spain.
Price-sales dilemma
Company spokesman Mark Truby said he could not confirm the 2012 figures and insisted Ford's turnaround was on track.
"Our incentive levels are below industry average among Europe's volume automakers," Truby said.
"We're fundamentally transforming our business in Europe by significantly increasing new product, improving our brand image and addressing costs."
The company's stock has risen 6.5 percent to $13.36 over the past 12 months, compared with a 16.4 percent gain for GM.
The new Fiesta and Kuga models posted stronger orders in February, Ford said this week, promising to revive deliveries ahead of the late-2013 arrival of its EcoSport mini crossover.
Carmakers from Daimler AG to Renault have also warned that European demand continues to weaken.
But responses have varied, with brands like Renault and Opel vowing to maintain market share while GM's Chevrolet and others give ground to defend prices.
Ford has yet to resolve the dilemma between pricing and market share, which may deepen as German premium brands compete more aggressively against its mid-market cars, some observers say.
"It's going to be difficult," said Tom De Vleesschauwer of consulting firm IHS Automotive. "It seems impossible in the current climate to have both."
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