Shane van Gisbergen and Craig Lowndes’ preparations for the Bathurst 12 Hour have been hampered by a throttle issue with their McLaren in final practice.
The #58 McLaren being shared by the Supercars champions and Frenchman Come Ledogar completed just three laps in Practice 5.
Van Gisbergen went out at the start of the session to bed brakes, but was soon back in the garage while YNA Autosport traced a throttle issue.
The car did not reappear for the remainder of the 55 minutes, which was the final track time ahead of qualifying.
Speaking directly after the session, Lowndes told Supercars.com that the team is still chasing the issue, but should have it rectified for qualifying.
"Shane was talking about something to do with the throttle, that it’s gone into a limp-home mode," he explained
"We got it back, we're just trying to figure out whether it’s electrical or mechanical.
"They’re pretty confident they can get it out there for qualifying. We’ll see what happens.
"Shane’s the one that’s going to qualify, so I’ll go out, give it a run, give it a shakedown and then hand it over to him."
The trouble follows a lacklustre Friday for the highly-fancied entry, which ended the day with a 2:05.0s from Lowndes as the car's best.
"It was a bit frustrating to be honest, with all of the stoppages and red flags and the sessions being time certain, I think I did about eight laps," he reflected.
"But the car feels good, from the laps that we did. It feels alright, so that’s a good start."
Audi and BMW, meanwhile, carried their strong Friday form into Practice 5, locking out the first five places.
They were led by the two Jamec-Pem R8s; Christopher Haase clocking a late 2:03.0618s best to knock Garth Tander’s entry to second.
Tander spent the final part of the session in the car, but its fastest time was clocked earlier by impressive Bathurst rookie Kelvin van der Linde.
Marco Wittman put the BMW he is sharing with Augusto Farfus and Chaz Mostert third, with the Supercars ace sitting out the session as his co-drivers clocked laps.
Jamie Whincup took over the SunEnergy1 Mercedes from amateur co-driver Kenny Habul for the final minutes and put the AMG into sixth.
Elsewhere, Tim Slade’s McLaren ended up 10th, David Reynolds’ Mercedes 16th, Will Davison’s Audi 23rd, Scott McLaughlin’s McLaren 24th, Cameron Waters’ Mercedes 30th and Lee Holdsworth’s Audi 32nd.
The session was interrupted by two red flag periods, triggered by a spin at the Cutting for the #66 Dodge Viper and a heavy crash for the #94 MARC Focus at Reid Park.
Qualifying will take place over three parts, with an all-in session from 11:05am, before Class A cars have a 30-minute block to themselves from 11:55am, and a Top 10 Shootout from 4:15pm.