The start of the Bathurst 1000 has been dramatically delayed after a wildcard entry was forced to exit his Holden with carbon dioxide poisoning.

There was drama before the 161-lap epic enduro even began when Brodie Kostecki struggled to breath and failed to complete the formation lap just moments before the race was about start.

A driver cooling system failure in the Commodore forced Kostecki to stop at the top of Conrod Straight and he was taken to the medical centre, forcing his cousin and co-driver Jake to start.

The team received permission for another cousin Kurt Kostecki to replace him, saying Brodie was ill after breathing in fumes.

He suffered burning eyes and breathing difficulties as a result of a problem with his helmet fan, suffering carbon dioxide poisoning.

But Brodie Kostecki was later cleared to drive after he was assessed in the medical centre where he received oxygen and also underwent a concussion test.

“It was pretty scary but yeah, I’m back,” Brodie Kostecki said.

The incident caused a 15-minute delay to the race start with Jake Kostecki forced to begin from pit lane after their Commodore was towed back to the garage.

It initially did not look good for Brodie Kostecki’s return with team official Paul Morris telling TV reporters he was concerned by his driver’s condition.

“Obviously he’s pretty crook but we’ve got Kurt here who was on the podium in the Super2 race (support category),” Morris said.

“It makes sense to do it (replace driver). It’s been done before, not at this late notice.

“But we’ll see where Brodie is first but he didn’t look too healthy.”