Holdens hit trouble

The additional driver practice session at Sydney Motorsport Park was punctuated by mechanical issues for two of the key Holdens, bringing out two red flags in the 30-minute run this morning.

Dean Fiore, in Michael Caruso's Nissan, was quickest over Cameron Waters by just 0.05sec with a 1min31.5627 lap.

But all eyes will be on TEKNO Autosports and Holden Racing Team as they look to solve the problems affecting their race cars before the next session, kicking off in less than an hour's time.

Jonathon Webb, behind the wheel of the Darrell Lea STIX Commodore of Shane van Gisbergen was the first to strike trouble, immediately shutting down his Holden at the exit of turn two 12 minutes into the session. The car was running eighth at the time.

Van Gisbergen won two of the three races at Sydney Motorsport Park last year and he and Webb have been billed one of the strongest pairings for the PIRTEK Enduro Cup.

The session was called with just over three minutes remaining, when smoke poured from the HRT #22 with Jack Perkins in the car.

"The HRT car looks like a major - they'll struggle to get that out for the first session," six-time champ Jamie Whincup mused, watching on from pit lane.

However team boss Adrian Burgess seemed calm in the red garage.

"It's lost an oil line or something, whether there's damage or anything we'll fix it and get back out. It's early days," he said.Courtney performed well at the circuit last year, but suffered from a gearbox issue in Sunday's 200km race when running at the front of the field.

Click here for full results from the co-driver session.