The mechanic responsible for servicing Wollongong solicitor Katie Foreman's Holden Astra car discovered large amounts of water in the vehicle's petrol tank twice in the year before she died, a court has heard.
Ms Foreman's mechanic, Jason Reid, provided two statements to police in the wake of her October 2011 death in which he said he removed "about two to four litres" of water from the fuel system after she brought the car to him twice in less than six months with the complaint it had been "playing up".
Multiple witnesses, including Ms Foreman's father Neil, have previously told jurors in the Supreme Court trial of her alleged killers that Ms Foreman had raised concerns about her car being tampered with before she died, and was unsure who may have been responsible.
Mr Reid said he was introduced to Ms Foreman through Neil, who he picked up as a client when he took over another business in 2006.
Mr Reid subsequently began servicing Ms Foreman's car around the same time, carrying out general servicing and repairs.
However, the court heard on two occasions in the year before Ms Foreman was killed, Mr Reid had been forced to flush out the entire fuel system in the vehicle after discovering it had been contaminated with water.
Of the first occasion, in November 2010, Mr Reid said he found the situation "a bit uncommon", but noted that cars could pick up water-contaminated fuel from service stations on occasion.
However, when Ms Foreman returned just five months later with the same problem, Mr Reid labelled the occurrence "strange".
"For it to happen twice in such a short time frame is very uncommon," he said in his first statement to police in early 2012.
In a second statement, Mr Reid said he removed "quite a bit" of water from the fuel system - an estimated two to four litres each time.
He also noted in one of his statements that Ms Foreman had bought and installed on the Astra a lockable fuel cap, which required a key to open the petrol tank.
The trial continues.