Interested in buying a car because of those payment protection plans, where the automaker agrees to make payments if you lose your job? You may need to move quickly. The plans are coming to an end one by one.

In April, General Motors and Ford followed Hyundai's lead by announcing payment protection plans. The details differed between automakers, but the essence of the plans was the same: if a new car buyer lost their income in the first year of ownership, the automaker would pick up the monthly payments on the car for a certain period of time, without negative effect on the buyer's credit.

Kicking Tires notes that Ford's Advantage Plan faces a June 1 expiration date, "and with the economy showing signs of life, it's unlikely Ford will extend the plan." Hyundai's Assurance Plus Program, meanwhile, "ends June 30."

According to Kicking Tires, "GM's similar plan ended April 30," but a GM website advertising the Total Confidence program posts a June 1 end date, thought it notes, that "Saab, Hummer and Cadillac vehicles, medium duty and heavy duty trucks are excluded."

May auto industry sales figures are not yet available, but based on April numbers, the plans seemed to have little impact on consumer behavior. Jack Nerad, editorial director for Kelley Blue Book, told CNN that "Job-loss based incentives may have worked for Hyundai, which was first to offer a payment-protection plan, they didn't have the same effect for General Motors or Ford. That's because the newness factor of the protection plans had already worn off by the time the American automakers announced their versions."

The plans, however, remain in effect until Monday -- so if you are interested, act quickly.

If you're in the market for a new car, check out the U.S. News rankings of this year's best cars as well as this month's best car deals.