Mr. Obama told autoworkers at Daimler Detroit Diesel Plant that he will fight to extend tax cuts for the middle class.
"If Congress doesn't act soon, meaning in the next few weeks, starting on January 1st, everybody's going to see their income taxes go up," he said as the crowd booed. "It's true. You all don't like that."
The president dialed back his criticism of Republicans compared with other recent appearances, only mentioning the word "Republican" twice in the 23-minute speech.
"We can solve this problem. All Congress needs to do is pass a law that would prevent a tax hike on the first $250,000 of everybody's income," Mr. Obama said.
On Sunday, the president met privately with House Speaker John Boehner at the White House. It was their first face-to-face meeting in three weeks. While there was no apparent resolution, the two camps issued the same statement afterward.
The stalemate is centered on whether taxes should be raised on the wealthiest Americans. The president has toughened his demands in recent days, insisting not only that tax rates must rise, but also that Congress give him and future presidents the authority to raise the government's borrowing limit without prior approval by lawmakers.
If a deal is not reached by Jan. 1, income taxes will go up for nearly all Americans.
ABC News and The Associated Press contributed to this report.