(Adds second-quarter sales results, details, background, analyst estimates)

Aug 19 (Reuters) - Rental car company Hertz Global Holdings Inc said on Tuesday it is withdrawing its full-year financial forecast and expects 2014 results to be "well below" its previous guidance due to business challenges and costs related to a review of the past three years' results.

The company said in a regulatory filing that its full-year results would be affected by operational challenges, including recalls by car makers, higher-than-expected operating expenses and weak demand in its equipment rental business. (http://1.usa.gov/YwpVmG)

The company previously forecast full-year 2014 adjusted profit of $1.70 to $2 per share on revenue of $11.4 billion to $11.7 billion.

Analysts on average expected profit of $1.82 per share on revenue of $11.48 billion, according to Thomson Reuters I/B/E/S.

In addition, the company said on Tuesday the divestiture of its equipment rental business, announced in March, could be delayed beyond the previously announced early 2015 date due to its accounting review.

Hertz said in June that it would restate or correct financial results for the past three years to fix accounting errors originating in 2011.

The company previously said it had identified errors totaling $46.3 million in prior periods.

In Tuesday's filing, the company said second-quarter U.S. rental car revenue increased 4 percent, while rental car revenue-per-day rose 2 percent.

Limited fleet availability due to recalls by car manufacturers hurt U.S. rental car revenues, Hertz said.

International rental car revenue rose 7 percent, driven by higher demand in Europe and New Zealand, and its worldwide equipment business recorded sales growth of 1 percent.

The company, which has yet to report its first-quarter results, said this month it would be unable to report second-quarter results by Aug. 11, citing the accounting review. (http://bit.ly/VDNKa0)

The company warned in May that it would not report first-quarter results on time and said it had identified errors that might cause it to restate its 2011 financial statements.

At the time, Hertz said it needed to do more work related to evaluating the capitalization and depreciation timing for "certain non-fleet expenditures." The company said adjustments, including for allowances for doubtful accounts in Brazil, would likely reduce its 2011 net income by as much as $9.8 million, to $174 million.

Hertz's accounting problems come as the car rental industry is picking up because business and leisure travel is increasing along with an improving economy in the United States.

However, Hertz has not been able to benefit, partly due to higher expenses. The company's adjusted net earnings fell 13 percent in the 2013 fourth quarter.

Hertz, under pressure from investors to focus on car rentals, had said in March that it would spin off its equipment rental business, raising $2.5 billion to reduce debt and fund a $1 billion share buyback.

(Reporting by Ramkumar Iyer in Bangalore; Editing by Leslie Adler and Cynthia Osterman)