Jan.17 (GMM) Red Bull's new car for 2008 survived a scare on its installation lap before breaking down at the end of its first day of running at Jerez.

The RB4 was launched at the Spanish circuit earlier on Wednesday, before David Coulthard put 54 laps on its odometer.

On the very first out-in lap, Scot Coulthard - who like all Red Bull personnel is hoping for a more reliable season for the team - feared a throttle problem, but it turned out to be a false alarm.

Ultimately, Adrian Newey's second car designed at Milton-Keynes was a few tenths slower in the patchy rain than the 2007 version, which completed a similar number of laps in the hands of Mark Webber.

"The car's potential? Far too early to say!" Newey said, after Coulthard walked back to the pits following an engine problem with a few minutes of the session left to run.