With the lunch break at Sydney Motorsport Park fast approaching, Randle has only turned a total of eight laps in his Tickford Ford.
None of those were timed laps, the second-year racer struggling with a delayed throttle response.
The car is currently being worked on by a group that includes staff from Ford engine supplier Herrod Performance Engines, Supercars, and the team itself.
According to Randle the issue has put a serious dent in what is his final pre-season hit-out ahead of the season opener in Newcastle.
"It's a disappointing because this is the official pre-season test and we had a really good test plan in place," Randle told Motorsport.com.
"But we haven't been able to execute any of our programme.
"Our guys have been working hard with the Herrod, Ford and Supercars technical guys to find what is causing the issue. But it's hard to drive the car with the issue we have right now."
Following a damp start to the day, conditions have improved a SMP with the field now circulating on slick Dunlop tyres.
James Courtney is currently the best-placed Tickford driver sitting in 14th with Cam Waters 21st and the Declan Fraser car, being shared in his illness-induced absence by the co-driver pool, 24th fastest at the time of publication.
