Fastexy Exchange|Ford's recall of Bronco and Escape raises "significant safety concerns" federal regulators say

Investigation into Ford crashes involving Blue Cruise

Federal regulators are questioning the method that Michigan automaker Ford took to repair thousands of SUVs it recalled early last month. 

In April, Ford recalled nearly 43,000 Bronco Sports and Escapes SUVs because gasoline can leak from the fuel injectors onto hot engine surfaces, increasing the risk of fires. Ford said the SUVs have fuel injectors that will crack, allowing gas or vapor to leak near the hot engine parts. 

Ford's remedy for the defect was to add a drain tube to send the gas away from hot surfaces, and a software update to detect a pressure drop in the fuel injection system. If that happens, the software will disable the high pressure fuel pump, reduce engine power and cut temperatures in the engine compartment. 

But the U.S. National Highway Traffic Safety Administration (NHTSA) says the tube method doesn't actually fix the problem. 

In a letter to Ford released Thursday, the NHTSA said its Office of Defects Investigation has opened an investigation into the recall, noting "significant safety concerns" about Ford's repair method. The NHTSA added that it "believes the remedy program does not address the root cause of the issue and does not proactively call for the replacement of defective fuel injectors prior to their failure."

Ford said Thursday that it is working with the NHTSA during its investigation. Ford said the Bronco Sport and Escape recall is an extension of a 2022 recall for the same problem. The repair has already been tested on vehicles involved in the previous recall.

In its letter, the NHTSA is asking Ford to send the agency details about the fuel injector fix, including any testing the company conducted to verify that their remedy resolved the fuel injector problem and the question of whether hardware repairs were needed. NHTSA is also asking the company to explain any other remedies that were considered and any cost-benefit analysis the company did when it selected the fix.

The agency also wants to know how much fuel will leak and whether the amount complies with federal environmental and safety standards. It also wants to hear Ford's take on "its obligations (legal, ethical, environmental and other) to prevent and/or limit fuel leakage onto the roadway at any point during a vehicle's lifespan."

NHTSA is also asking Ford to detail how the software will detect a fuel pressure drop, how much time elapses between cracking and detection, and what messages will be sent to the driver. It also asks what effect disabling the high-pressure fuel pump has on other fuel system parts, and how the SUVs will perform when the pump is disabled.

Ford has to provide the requested information to NHTSA by June 21, the letter said. Depending on the results of its investigation, the agency can seek additional repairs that fix the fuel leaks.

—The Associated Press contributed to this report. 

Khristopher J. Brooks

Khristopher J. Brooks is a reporter for CBS MoneyWatch. He previously worked as a reporter for the Omaha World-Herald, Newsday and the Florida Times-Union. His reporting primarily focuses on the U.S. housing market, the business of sports and bankruptcy.

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