Michigan’s Congressional delegation on Thursday urged Treasury Secretary Henry Paulson and Federal Reserve Chairman Ben Bernanke to hurry up and use their newly granted regulatory authority to loosen up lines of credit to help finance auto loans.

In a letter to the nation’s two top financial administrators, the lawmakers point to the country’s “dramatically depressed vehicle sales” and say these conditions are putting a vast network of businesses at risk, not just car manufacturers. The Members, whose state is home to the nation’s largest domestic automakers, highlight that one in 10 American jobs is related to auto manufacturing.

“The disappearance of liquidity in credit markets, if not relieved in coming weeks, threatens to cripple these industries and the communities in which they operate,” the Michigan lawmakers wrote.

In a separate statement, Energy and Commerce Chairman John Dingell (D), also of Michigan, warned that domestic car manufacturers face the most difficult conditions they have seen in decades. The Michigan delegation noted that new car sales fell 26.6 percent in September and are expected to fall by 30 percent this month, which brings the industry to the lowest annualized rate since 1983.

“We need to do something to help unfreeze the credit markets for that industry, as well as all others. The Michigan delegation is pursuing all options and asking that the Bush Administration — Treasury, Fed, FDIC — also consider all available options,” Dingell said.

Rep. Tim Walberg (R) is the only member of the Michigan delegation whose name isn’t on the letter, but Walberg’s spokesman said he did sign it, and there was a “miscommunication of some kind” that led to his name being left off.