Mr Andrews batted away questions after a young man seriously injured in a crash with his taxpayer-funded car in 2013 cast doubt on the Victorian premier's version of events, and engaged a lawyer.

Ryan Meuleman was knocked off his bike at Blairgowrie on the Mornington Peninsula in a collision with the then opposition leader's 4WD.

Mr Andrews' wife Catherine was driving at the time, with Mr Andrews and their three children passengers.

The smash left the then 15-year-old Mr Meuleman in Melbourne's Royal Children's Hospital, where he underwent surgery for his injuries.

Now 24, he has revealed he was visited by police on the day he returned home from hospital but tubes removed from his throat prevented him telling his story.

"They did not come back at any time thereafter to get a statement from me," Mr Meuleman told the Herald Sun.

Mr Meuleman claims the Andrews' car was speeding and he was riding his sister's bike very slowly.

In contrast Mr Andrews told reporters in 2017 the young cyclist was moving at speed before being T-boned by the car.

The Labor leader was asked 17 consecutive questions on the matter, referring journalists to his previous comments.

"I've canvassed those matters in great detail and I've got no further comment to make," he told reporters on Thursday.

An $80,000 payment from the Transport Accident Commission was made to Mr Meuleman, but his family have expressed concern about the process. He has now engaged a lawyer to explore his legal options.

Mr Andrews left the scene after calling triple zero, citing the need to take his children to their nearby holiday rental before returning.

His wife wasn't breath-tested, with then police commissioner Graham Ashton later conceding the officers had "mucked up".

No charges were laid over the crash and IBAC cleared police of wrongdoing.

After handing out treats on the campaign bus and speaking to assembled media in Ballarat on Wednesday, Ms Andrews was a no show.

Her husband said she hadn't planned to attend Thursday's event at Epping, where Labor pledged $44 million to provide new medical scanning equipment for eight hospitals if re-elected on November 26.

"She's working today. She's got a day job," Mr Andrews said.

Although sharing a dental pledge, Liberal liberal Matthew Guy was far from grinning as he faced more questions over the coalition's backfiring "Ditch Dan" ambulance stunt.

Mr Guy said he hadn't seen the vehicle on Thursday when asked if it still was emblazoned with the word "ambulance", in apparent breach of the Ambulance Services Act.

"But I do know is it has a political authorisation on it. It had one yesterday too," he said.

"And an authorisation denotes something as political advertising, which is what we thought it was."

Mr Guy was in Doncaster to promise up to 32,000 dental vouchers in a bid to halve the state's 64,000-strong public dental waiting list within two years.

The $500 vouchers are expected to cost about $16 million, on top of another $200 million coalition commitment to boost public dental services over the next four years.

Australian Associated Press