Stewards issued Coulthard a penalty during the race after the championship leader made contact with the rear of Percat's Brad Jones Racing Commodore at Turn 11.
Percat ran wide at the corner before copping a hit as he tried to recover the car in the slippery wet conditions.
Coulthard feels the incident didn't warrant a 15 second penalty, claiming that he had nowhere to go to avoid hitting Percat.
The New Zealander felt the clash was not as bad as others that copped the same penalty during the race.
A similar sanction was issued to car #88 of Jamie Whincup and Paul Dumbrell after the latter clouted Steve Owen (#55 Prodrive) at the first chicane.
“The penalty was the icing on the cake,” Coulthard told Speedcafe.com.
“You compare incidents, mine was far less of an incident than the one between the #55 and #88 (at first chicane).
“I feel a little bit hard done by but the call has been made I will cop it and move on.
“He was a little bit out of control on the way in and struggled to get to the apex and just defended hard. I don't know what else I was supposed to do.
“I was there and I was getting pushed from behind (by Rick Kelly) too.”
He did confirm that he would speak to the Shell Ford driver later this evening.
“It is interesting, I was obviously a little bit wide, but didn't expect to get turned around, because it is not what we do,” said Percat.
“I will speak to Fabs later, I just wanted to celebrate with the BJR guys to be honest.”
Percat disagreed at the notion that the incident was triggered by Coulthard being pushed by Rick Kelly's following
“I wouldn't have thought so, I think Fabian has a brake pedal,” he responded.
Meanwhile, Coulthard leads the championship 37 points from Jamie Whincup ahead of Sunday's Race 22.