The U.S. government’s auto safety regulator has ended a 2 1/2-year investigation into Ford engine failures after the company replaced engines or extended the warranty on some vehicles.

The National Highway Traffic Safety Administration says in documents posted Monday on its website that its analysis traced the problem to intake valves that can fracture inside some 2.7-liter and 3-liter turbocharged engines. Documents say the probe opened in May of 2022 ended up covering more than 411,000 vehicles from the 2021 and 2022 model years including the Ford F-150 Bronco, Edge and Explorer as well as the Lincoln Aviator and Nautilus.

The agency was looking into catastrophic engine failures caused by intake valves fracturing, dropping into the cylinder and hitting the piston.

An analysis of failure report data found that the faulty valves were made from May through October of 2021, the agency said.

Earlier this year Ford recalled about 91,000 vehicles with valves made during the suspect period. They’ll be tested and get a new engine if necessary. The company also extended the warranty on vehicles with valves made during the period to 10 years or 150,000 miles, the documents said.

Nvidia replaces Intel on the Dow index

Nvidia is replacing Intel on the Dow Jones Industrial Average, ending a 25-year-run for a pioneering semiconductor company that has fallen behind as Nvidia cornered the market for chips that run artificial intelligence systems.

Paint-maker Sherwin-Williams will also replace chemical company Dow Inc. among the companies that make up the 30-stock average.

S&P Dow Jones Indices said Friday that the changes that take effect Thursday “were initiated to ensure a more representative exposure to the semiconductors industry and the materials sector respectively.”

Dow Inc., a major producer of chemicals and plastics and unrelated to the similarly named company behind the index, has also been the smallest company on the Dow in terms of market capitalization.

Intel’s share price has dropped more than 50% so far this year to $23.20. On Thursday, the California chipmaker reported third-quarter revenue of $13.3 billion, down 6% from the same period last year.

X opens posts to blocked accounts

Elon Musk’s X has been modified so that accounts you’ve blocked on the social media platform can still see your public posts.

X updated its Help Center page over the weekend to explain how blocking now works on the site.

While you can still block accounts, those accounts will now be able to see your posts unless you have made your account private. They won’t, however, be able to reply to them or repost them. Blocked accounts also won’t be able to follow you and you won’t be able to follow them, as has been the case before the policy change.

In addition, if the owner of an account you blocked visits your profile on X, they will be able to learn that you have blocked them. X indicated that the change was aimed at protecting users who have been blocked.

Critics say the changes could harm victims and survivors of abuse, for instance. Thomas Ristenpart, professor of computer security at Cornell Tech and co-founder of the Clinic to End Tech Abuse, said it can be critical for the safety of survivors of intimate-partner violence to be able to control who sees their posts.

“We often hear reports about posts to social media enabling abusers to stalk them or triggering further harassment,” he said. “Removing users’ ability to block problematic individuals will be a huge step backwards for survivor safety.”

Compiled from Associated Press reports.