Hooting at a woman about to hit their car in the drive-thru at a Wollongong McDonald's turned into a six week-long nightmare for an Illawarra family that culminated in their Ford Ranger exploding in the household's driveway in the middle of the night, police will allege.

A "relatively minor" altercation between a couple and a woman at the 24-hour Warrawong McDonald's on February 22 led to a prolonged alleged stalking and harassment campaign by the woman and her partner, who was not present at the time of the altercation, counter-terrorism and special tactics command's Detective Superintendent Michael McLean told reporters on Tuesday.

A couple who beeped at a woman about to hit their ute at the Warrawong McDonalds Drive Thru were allegedly stalked and intimidated by the woman in the other car over six weeks. Credit:Kylie Pickett

The woman at whom the couple hooted initially complained to Wollongong Police, then told her partner about the perceived slight.

The alleged "grievance-fuelled violence" began after what Superintendent McLean called "ingenious" methods were allegedly used to track down the couple who hooted.