By Agnieszka Flak and Bernie Woodall

MILAN/DETROIT (Reuters) - Fiat Chrysler Automobiles (FCA) nudged up its full-year adjusted earnings guidance on Wednesday, but its shares came off earlier highs after recall costs hit second-quarter profit and concerns remained about its exposure to a peaking U.S. market.

The world's seventh-largest carmaker said adjusted operating profit for April to June rose 16 percent to 1.63 billion euros ($1.8 billion), in line with an analyst consensus of 1.64 billion euros in a Reuters poll.

But earnings fell 14 percent when including charges related to recall costs and production adjustments in North America.

FCA <FCHA.MI> is investing billions of dollars - despite high debts - in a bid to capture a bigger share of the lucrative SUV and pickup truck markets in the United States. This includes $1.5 billion in a plant in Michigan and another $1 billion to retool assembly plants in Ohio and Illinois.

FCA's profit margins in North America rose to 7.9 percent in the quarter from 7.7 percent last year but the improvement was less marked than in previous quarters and failed to impress when compared with 12.1 percent for GM <GM.N>.

"Free cash flow was a touch better than anticipated, yet FCA's net debt remains elevated," said George Galliers, an analyst at Evercore ISI.

"Rightly, investors may be concerned given the fact that North American earnings growth would appear to be plateauing."

North America accounted for nearly 85 percent of FCA's quarterly profit, reflecting robust demand for its Jeep SUVs and pickup trucks. FCA broke even in Latin America and posted strong earnings growth in Europe.

FCA Chief Executive Sergio Marchionne applauded GM's margins, but said he expected FCA to get "very close" to those numbers once the retooling of its U.S. plants was completed.

He added he expected FCA to stop making passenger cars in the United States by the end of the first quarter 2017.

"Our biggest task now is to close the operating margin gap with our competitors ... we need to get off our butts and get that done," he said. He added management was increasingly confident the carmaker's targets to 2018 were achievable.

FCA raised its full-year guidance for revenues and adjusted operating profit and kept its debt projection intact, but analysts remained unimpressed, saying the revisions came close to where consensus expectations were.

Shares in the company, down 26 percent in the year to date, fell more than 3 percent after the results, but later recovered some losses and were down 0.2 percent by 1358 GMT.

In the second quarter, sales fell 2 percent to 27.89 billion euros, below expectations of 29.3 billion euros.

The automaker, which spun off luxury unit Ferrari <RACE.MI> at the start of the year, said net industrial debt fell to 5.5 billion euros at the end of June, down from 6.6 billion euros three months earlier, helped by strong cash generation.

(Additional reporting by Stefano Rebaudo; Editing by Alexander Smith and Mark Potter)