Mr Lyon also dove to the ground to evade the vehicle, after it collided with a road sign.
The woman had stopped, let the dog out, and then left again.
"I fell down and dislocated my shoulder and had a few bruises and sores."
Mr Lyon believed the woman who took his car had been involved in the accident that he had stopped to assist with.
"All this went for about 15 minutes. I was pretty shaken up.
"Just tried to do the honest Kiwi thing and help her."
Two fences near three holiday homes owned by the Miriam Trust, on the corner of Church St and Domain Rd, were damaged.
Technician John Rangihuna's family from Wellington occupied the holiday home closest to the knocked over fences.
Mr Rangihuna said he had feared for his 10-year-old daughter's safety as she stood on the front door of the holiday home.
"My brother-in-law had to jump out of the way to avoid being hit," he said.
The woman collided with a parked car and a police patrol vehicle before she was stopped by police on Tainui St.
Onerahi community constable Aaron Furze said she would go through a five-day mental health assessment before a decision would be made regarding charges.
A Northpower crew member was assessing the 11,400 volt transformer on Church St yesterday which slightly shifted from the impact.