They thought a swerving Hastings driver was on drugs. But that wasn't the problem.

Onlookers calling police were concerned the driver on Pukatea St might be impaired by drugs or alcohol. Photo / Google Maps

Police who pulled over a car seen swerving dramatically from side to side on a Hawke's Bay street weren't expecting the driver's novel excuse.

The man's erratic driving on Pukatea Street in Saint Leonards, Hastings, prompted multiple calls to police by onlookers concerned he might be impaired by drugs or alcohol.

Police pulled him over at 12.30pm on Wednesday.

The driver explained to them that his car was running out of fuel.

He was trying to get whatever was left of the fuel swishing around in the tank in an attempt to get his car keep going, he told police.

The driver was spoken to and no further action was taken, a police communications spokesman said.