When it comes to gas prices, we may have found the elusive "tipping point."

Cars.com recently completed a survey of motorists that found that 85 percent of consumers would respond to a prolonged period of $4 gasoline prices by buying a more fuel-efficient car.

(ENLARGE)

If the price of gasoline continues to rise at the pump, signs like this won't be much of a laughing matter. Most consumers say $4 per gallon is the magic number that will have them looking to buy more fuel-efficient vehicles. But just as they don't want to pay more at the pump, they don't seem to want to pay more at the dealership either.

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Among those who said that they would buy something that uses less gas, 28 percent said they would do so immediately and 57 percent said they would do it the next time they bought a vehicle.

Most consumers in the survey said they are already trying to cut gas consumption. Keeping tires properly inflated, running multiple errands in one trip and avoiding sudden stops and rapid acceleration were among the tactics drivers said they are using.

"The survey is consistent with what we are seeing when it comes to searches for fuel-efficient vehicles," Patrick Olsen, editor-in-chief of Cars.com, said in a statement. "When gas prices surged past $3 a gallon, searches for fuel-efficient vehicles skyrocketed. With no end in sight to soaring gas prices, I would expect that we are going to see more people seeking out cars that get better than 30 miles to the gallon."

Almost three-fourths of survey respondents said that 30 mpg or better is their target for fuel efficiency in their current or future vehicle.

But people don't want to replace spending money at the pump with spending money at the dealership.

When asked how much more they would pay for a car that got 40 miles per gallon vs. a car that got 25 miles per gallon, more than 60 percent set their limit at $2,000 and 21 percent said they wouldn't pay any more for it.

"Clearly, when it comes to fuel-efficiency, there is a contradiction between what consumers want and what they are willing to pay for," Olsen said. "That puts a bigger burden on auto makers who claim that they will have to add thousands of dollars to the cost of each vehicle to meet the fuel-economy standards of 35 miles per gallon by 2020."