A north Queensland mother who took out a $10,000 loan to purchase a second-hand family car says she feels powerless after being left to pay off a debt for a vehicle that does not work.

Michelle Thomas' experience is among a growing number of cases piling up before Queensland's Office of Fair Trading (OFT) about used car sales, with consumer advocates saying vulnerable people are falling victim the most. 

Prolonged supply chain shortages in the global car industry since the onset of the COVID-19 pandemic has meant demand for used cars was at a premium.

Ms Thomas said she bought her seven-seater dream car in Cairns during April for her big family, but her joy was short-lived when it broke down a week later.

"I just felt it, you know. I've been driving for over 20 years."

Ms Thomas said she took her car to a mechanic within weeks of purchase and discovered it had a major oil leak.

"They couldn't diagnose the problem without cleaning up all the oil under the motor," she said.

"That would have cost me $1,600 and I didn't have that kind of money laying around."

She admitted that she did not undertake the recommended necessary mechanical checks before purchase but paid for an extended warranty.

Ms Thomas said after constant back and forth with the dealership, her car had been sitting with the dealer for months.

"I've been waiting for them to fix it ever since," she said.

"I pay the loan and I paid that extended warranty and it's almost up.

"It's six months since I bought the car."

Thousands of complaints state-wide

The OFT said the motor industry was one of the most complained-about sectors in the state.

Across Queensland, it had received more than 13,000 complaints in the past five years, with 792 of those from Townsville and Cairns.

There have been 34 prosecutions across the state during that time relating to the motor industry.

Jillian Williams from the north Queensland-based Indigenous Consumer Assistance Network said the organisation had been fielding increasing calls from second-hand car buyers.

"At the moment it is close to once a week," Ms Williams said.

"It's certainly very regularly coming through our door — people who are struggling either with a car loan or with a car that they've bought, which broke down within months of purchase."

The consumer support group said people were particularly vulnerable because the used car market was so hot.

"In many of the cases, we see the cars themselves are a very poor quality and not worth the cost, or the sale price that they were sold and they're breaking down very quickly," Ms Williams said.

"I think some dealerships definitely take advantage of people simply not knowing.

"Most people in the community don't know how to check whether a car is of good quality or not. It's a pretty expert area."

Dealership responds

The car dealership from where Ms Thomas purchased her car said each vehicle was independently inspected for a Certificate of Inspection.

"It is important to remember we sell used vehicles, which may be older vehicles and hence may be more prone to issues," a spokesperson said.

"We do our best to rectify any issues brought to our attention as soon as possible.

"There are three common issues we have with vehicles failing after purchase — topping water up when the car is overheating and not addressing the problem early on; not checking oil properly and over filling the engine; and electrical issues."

He said the majority of vehicles that have remained at their yard "for any length of time have not been under statutory warranty and have in fact been misused by the customer".

Lemon laws introduced

The Queensland government introduced lemon laws in 2019 in a bid to provide better protections for people purchasing used cars, but Ms Williams said the process of lodging a claim through the Queensland Civil and Administrative Tribunal (QCAT) was not straightforward.

She said introducing an ombudsman to investigate complaints would help.

"It needs to be free to the consumer with internal mechanical experts who can inspect the vehicle," Ms Williams said.

"The decisions need to be binding on the dealership."

Calls for action

Consumer advocacy group Choice has been looking into the issue and is calling for action to clean up the industry.

"[And] more firm and consistent action from OFT in Queensland against the dealerships that have had multiple complaints over many years," Choice spokesperson Jarni Blakkarly said.

Mr Blakkarly said the federal government also had a role to play.

"The government is currently looking to legislate stronger penalties under consumer guarantees when businesses fail to follow Australian Consumer Law," he said.

"So that's something that would also potentially help people in this situation."

Waiting in limbo

In the meantime, Ms Thomas has borrowed a small car while she remained in limbo about her own vehicle.

She hopes others can learn from her experience.

"Just be careful where you're buying cars from," Ms Thomas said.

"Take it for a test drive and get a check."