Rod Camilleri was driving from Canberra Airport to his home in Kameruka on January 20 when he stopped to fill his car with 70 litres of diesel from the United service station.

When he arrived home two hours later, his car would no longer start.

"As soon as I got home the car stalled and it had less than 15,000 kilometres on it," he said. "It just wouldn't start again.

"It was sent to a diesel specialist and the fuel was found to be contaminated."

When Mr Camilleri called the service station, he was told at least two other people had already notified the United station about fuel contamination.

While he was eventually refunded for 50 of the 70 litres he purchased from the service station, Mr Camilleri launched a claim with United to be reimbursed for the cost to fix his car, which was up to $12,800.

"By about April they decided to pay me back, but we never received a cheque or any money," he said.

The case went before the Civil and Administrative Tribunal on October 17, and while Mr Camilleri had signed a non-disclosure agreement waiver to receive the money, United refused to pay the money.

Mr Camilleri said United did not accept the form as they claimed it was a "draft copy".

A similar situation played out in the next meeting before the tribunal on October 25. Mr Camilleri said United refused to sign the document to acknowledge the payment, claiming it was not "legally binding".

United Petroleum did not respond to questions from The Canberra Times before deadline.

In the last financial year, 21 drivers in the ACT lodged claims with their insurance provider about fuel contamination.

However, the data does not reveal which service stations the contaminated fuel came from.

A spokeswoman for consumer advocacy group Choice said it was often difficult for drivers to get a fuel company to claim responsibility for damage caused by contaminated fuel.

"If you don't have a receipt, the service station can avoid liability," she said. 

"If your car has been damaged, you need a mechanic's report pointing to dirty fuel as the cause, and even then the petrol station may not agree to foot the repair bill."

The Choice spokeswoman said fuel payments were protected under Australian Consumer Law.

"Our previous investigation found petrol station operators playing hardball with victims' consumer rights when they served up dirty fuel," she said.

Mr Camilleri is hoping other drivers affected by the fuel contamination will come forward in the hope of strengthening the consumer case against United.

"United are telling us they want some evidence that it's their fault that it happened," he said.

Do you know more? andrewbrown@fairfaxmedia.com.au