2003 Holden Other Zafira

This is a real common problem on Chrysler products and has an easy fix. Yours may be the same. The Engine Computer loses its memory when it or the battery is disconnected, then it has to relearn "minimum throttle" before it will know when it has to be in control of idle speed. To meet the conditions for that relearn to take place you have to drive at highway speed with the engine warmed up, then coast for at least seven seconds without touching the pedals. In the rare case that doesn't work it may help to hold the brake pedal up with your foot in case the brake light switch is out of adjustment. (There's multiple sections to that switch so the brake lights will not be on when they shouldn't be).

I only know the procedure for Chryslers. You may need to speak with one of the mechanics at the local dealership to find out the secret.