British Touring Car racer Gordon Shedden has lost his fourth place from the third race at Brands Hatch on Sunday.
After a red flag for a multi-car accident, the Honda driver charged through the field to finish fourth on the road after a day beset by car problems.
But his team has now been deemed to have worked on the car under parc ferme conditions during the red flag period. He was therefore disqualified.
"Everything that can go wrong has gone wrong this weekend," Shedden said.
The decision leaves Shedden 11th in the championship table, 41 points behind leader Jason Plato.