Holden Barina 2007: Stalling and losing revs?

I was wondering if anybody else has had big issues with their 2007 TK Holden Barina continually stalling and losing revs on start up. So far I have spent over $1000 on this fault and Holden still do not know what the problem is. The computer was reset, the EGR valve was checked and pipe changed, the spark plugs and injectors cleaned. If Holden does not know or won't admit to this fault, then what is somebody supposed to do with these cars?