The man, in his 70s, crashed his car in Bank End in Cumbria just after 17:00 BST on Saturday.
Cumbria Police said residents and motorists rushed to help and gave first aid until an air ambulance arrived.
But a spokesman for the force said the man, who has not been formally identified, died at the crash site between Duddon Bridge and Ulpha.
Passers-by tried to save a crash victim by giving first aid at the side of the road, police have said.