... because she couldn't afford to have the nail taken out of her damaged tyre.
She's not alone.
National research released this week by Bingle Car Insurance shows that 55 per cent of Australians are cutting back on car maintenance.
"I was unemployed for six months so my little 1995 Mazda 121 took a back seat," says MacDonald, 32, now employed as a personal assistant.
"I got a nail in my tyre in March and I repaired it yesterday. I was driving around without a spare tyre for six months and trying to avoid glass and sharp things on the road. I had to wait for the cheapest day just to buy petrol and I took public transport for a while to save money."
Almost 60 per cent of Australian drivers claim the cost of running a car is rising faster than other living expenses such as gas and electricity, according to the research.
Bingle Car Insurance executive manager Ivan Owide says Newspoll research shows the average cost of running a car is $5556 a year including fuel, service, repairs, registration, insurance, and other costs, such as cleaning, detailing, tyres, parking and tolls.
"It's easy to see why people are already cutting back so they can stay on the road," he says. "The average Australian income is $67,000 per year before tax and $5556 represents a fair chunk of that, so it's not surprising that our research also found 75 per cent of Aussies think it's just too expensive."
Despite the cost of motoring, Bingle's national online survey of 602 motorists found that 92 per cent of Australians believe having a car is a necessity. While almost 70 per cent declare they would never give up their car no matter how much it costs to run, 22 per cent said they would sell their car if costs continued to grow.
The findings follow the release last month of auto car club figures on vehicle running costs which show costs have remained static over the past year. They claim falling finance costs and fixed-price servicing have offset rising fuel prices and new toll charges.