Fuel duty delay called for by Which?
Consumer organisation Which? is calling for a delay to the increase in fuel duty planned for January.
MPs will vote on Monday on the planned 3p a litre increase. Labour has previously said the increase should be postponed until at least April.
Which? said 85% of people it surveyed had expressed concerns about rising fuel prices.
Pollsters Populus interviewed 2,100 UK adults on behalf of Which? online between October 26 and 28.
The survey suggested 39% of people would cut back on motoring costs, while one in 10 said they had used savings to cover motoring costs.
Which? also said the figures showed 8.7 million households curbed their spending on essentials last month, while 6.4 million households used savings to cover outgoings.
The organisation's executive director Richard Lloyd said: "Rising fuel prices are the number one consumer worry and people are already telling us they're having to cut back and dip into savings just to get by.
"On the back of inflation-busting energy bill rises and increasing food prices, consumers can little afford another hit on their household budget. We're calling on the government to think again about their plans to increase fuel duty in January.
"The forthcoming Autumn Statement must focus on measures that will help put money back in the pockets of consumers, because the economic recovery is at risk if we don't increase consumer confidence."
Shadow treasury minister Cathy Jamieson said: "Families, pensioners and businesses are still feeling the squeeze. Labour will vote on Monday for a delay in this fuel duty increase at least until next April."
The duty increase was originally to be introduced last August, but in June Chancellor George Osborne announced that he was postponing it for five months.
At the time Mr Osborne told the Commons the delay was being funded by what he called "larger-than-forecast savings in departmental budgets."
A Treasury spokesman said: "The government recognises that the rising price of petrol is a significant part of households' day-to-day spending.
"Since coming to office the government has listened to the concerns of motorists about high pump prices and acted. Fuel is now 10p a litre lower than under the previous government's plans."