Manuel Balce Ceneta/Associated Press

Government investigators have found that JPMorgan Chase devised “manipulative schemes” that transformed “money-losing power plants into powerful profit centers,” and that one of its most senior executives gave “false and misleading statements” under oath.

The findings appear in a confidential government document, reviewed by The New York Times, that was sent to the bank in March, warning of a potential crackdown by the regulator of the nation’s energy markets.

The possible action comes amid showdowns with other agencies. One of the bank’s chief regulators, the Office of the Comptroller of the Currency, is weighing new enforcement actions against JPMorgan over the way the bank collected credit card debt and its possible failure to alert authorities to suspicions about Bernard L. Madoff, according to people who were not authorized to discuss the cases publicly.

In a meeting last month at the bank’s Park Avenue headquarters, the comptroller’s office delivered an unusually stark message to Jamie Dimon, the chief executive and chairman: the nation’s biggest bank was quickly losing credibility in Washington. The bank’s top lawyers, including Stephen M. Cutler, the general counsel, have also cautioned executives about the bank’s regulatory problems, employees say.

Mr. Dimon acknowledged in a recent letter to shareholders that “unfortunately, we expect we will have more” enforcement actions in “the coming months.” He apologized for letting “our regulators down” and vowed to “do all the work necessary to complete the needed improvements.”

JPMorgan’s Trading Loss

Still, the broad regulatory scrutiny — at least eight federal agencies are investigating the bank — presents a threat to JPMorgan at a time when it is raking in record profits.

For executives, the bank’s transition from model citizen to problem child in the eyes of the government has been jarring. It has helped drive top managers out of the bank, and it could make a coming shareholder vote on whether to split the roles of chairman and chief executive an anxious test for Mr. Dimon, long the country’s most influential banker.

Given the bank’s strong earnings, investors are unlikely to pull out. Yet a growing number of shareholders say they are concerned about the regulatory problems.

In the energy market investigation, the enforcement staff of the Federal Energy Regulatory Commission, or FERC, intends to recommend that the agency pursue an action against JPMorgan over its trading in California and Michigan electric markets.

The 70-page document also took aim at a top bank executive, Blythe Masters. A seminal Wall Street figure, Ms. Masters is known for helping expand the boundaries of finance, including the development of credit default swaps, a derivative that played a role in the financial crisis.

The regulatory document cites her supposed “knowledge and approval of schemes” carried out by a group of energy traders in Houston. The agency’s investigators claimed that Ms. Masters had “falsely” denied under oath her awareness of the problems and said that JPMorgan had made “scores of false and misleading statements and material omissions” to authorities, the document shows.

It is unclear whether the agency will file an action against JPMorgan based on the investigators’ findings. A majority of the five-member commission must first endorse the case. If the regulator does proceed, it could fine the bank and Ms. Masters.

“We intend to vigorously defend the firm and the employees in this matter,” said Kristin Lemkau, a spokeswoman for the bank. “We strongly dispute that Blythe Masters or any employee lied or acted inappropriately in this matter.”

JPMorgan has until at least mid-May to respond to the accusations in the document.

As the bank fights the energy investigation, it says it is trying to rectify other lingering compliance woes.

Recent departures from the bank, however, could complicate that effort. Frank J. Bisignano, the co-chief operating officer known for cleaning up JPMorgan’s troubled mortgage division after the 2008 financial crisis, announced his departure this week. Barry Koch, a senior lawyer with strong ties to law enforcement, is also expected to soon leave the bank, people close to Mr. Koch say.

Mr. Dimon’s meeting with the comptroller’s office last month further highlighted the bank’s challenges with regulators.

In the credit card investigation, people briefed on the case said the comptroller’s office had discovered that JPMorgan was relying on faulty documents when pursuing lawsuits against delinquent customers. The accusations, which are expected to prompt an enforcement action later this year, echo complaints that JPMorgan and rivals plowed through home foreclosures with little regard for accuracy.

In a separate investigation into JPMorgan’s relationship with Mr. Madoff, the comptroller’s office raised concerns that the company may have violated a federal law that requires banks to report suspicious transactions. Eventually, the people said, the agency could reprimand the bank for the potential oversight failures.

“We believe that the personnel who dealt with the Madoff issue acted in good faith,” Ms. Lemkau, the bank spokeswoman, said.

Some bank analysts also note that JPMorgan’s strong earnings could ameliorate concerns among its investors.

“As long as you’re making money, investors don’t care,” said Paul Miller, a managing director at FBR.

Regulators, however, increasingly do care. When the comptroller’s office sought documents in the Madoff case from JPMorgan, the bank declined, citing attorney-client privilege, according to bank employees. The dispute was then elevated to the Treasury Department’s inspector general, which oversees the comptroller’s office.

“The matter is pending,” said Richard Delmar, a counsel to the inspector general.

The Madoff case, authorities say, exposed a recurring problem at JPMorgan — what they say is its sometimes combative stance with regulators. In a recent report examining a $6 billion trading loss at the bank, Senate investigators faulted JPMorgan for briefly withholding documents from regulators. The trading loss has spawned several law enforcement investigations into the traders who created the faulty wager.

Mr. Dimon, who is not suspected of any wrongdoing, met this week with prosecutors and the F.B.I. to discuss the case, two people briefed on the investigation said.

A day before the Senate subcommittee released its report on the trading loss, JPMorgan received another ominous dispatch from Washington. On March 13, enforcement officials at FERC notified the bank that it planned to recommend an action over the power plant investigation.

JPMorgan is the latest big bank to face scrutiny from the energy regulator, which recently pursued actions against Barclays and Deutsche Bank. The cases reflect how the regulator has kept a more vigilant watch over the energy markets ever since the Enron fraud.

But Wall Street is fighting back against the new approach, casting the agency’s enforcement unit as overzealous and overreaching.

The JPMorgan case arose, according to the document, after the bank’s 2008 takeover of Bear Stearns gave the bank the rights to sell electricity from power plants in California and Michigan. It was a losing business that relied on “inefficient” and outdated technology, or as JPMorgan called it, “an unprofitable asset.”

Yet under “pressure to generate large profits,” the agency’s investigators said, traders in Houston devised a workaround. Adopting eight different “schemes” between September 2010 and June 2011, the traders offered the energy at prices “calculated to falsely appear attractive” to state energy authorities. The effort prompted authorities in California and Michigan to dole out about $83 million in “excessive” payments to JPMorgan, the investigators said. The behavior had “harmful effects” on the markets, according to the document.

JPMorgan disputes the claims, arguing that its trading was legal.

“The staff is challenging a bidding strategy that was transparent and was in full compliance with the applicable rules,” said Ms. Lemkau, the bank’s spokeswoman. “We strongly disagree with the staff’s conclusions.”

For now, according to the document, the enforcement officials plan to recommend that the commission hold the traders and Ms. Masters “individually liable.” While Ms. Masters was “less involved in the day-to-day decisions,” investigators nonetheless noted that she received PowerPoint presentations and e-mails outlining the energy trading strategies.

The bank, investigators said, then “planned and executed a systematic cover-up” of documents that exposed the strategy, including profit and loss statements.

In the March document, the government investigators also complained about what they said was obstruction by Ms. Masters. After the state authorities began to object to the strategy, Ms. Masters “personally participated in JPMorgan’s efforts to block” the state authorities “from understanding the reasons behind JPMorgan’s bidding schemes,” the document said.

The investigators also referenced an April 2011 e-mail in which Ms. Masters ordered a “rewrite” of an internal document that raised questions about whether the bank had run afoul of the law. The new wording stated that “JPMorgan does not believe that it violated FERC’s policies.”