Just a minor update for those interested. Got my car back this morning. Apparently they changed all 8 injectors (so including the one I paid for back in June). Complaint going off to Holden, will let you know how I get on (not really expecting anything from them, in which case I'll be taking things up with the ACCC).
Keep in mind that ACCC would be interested from the perspective of Holdens undertaking to them, to follow consumer law (and presumably ensure their franchisee's do the same). But ACCC generally don't get involved in individual consumer issues as such.
The fact your dealer charged you for injectors, for a vehicle only a month out of manuafcturers warranty, where these injectors should have lasted the life of the vehicle, is wrong. The dealer should have considered the ACL statuatory warranty, or even checked with Holden, which they seemingly failed to do. This as such would be a consumer affairs case (with interest to the ACCC as siad above). However, Holden should help sort out their franchisee's consumer law failure if presented to them in the correct light of their undertaking to ACCC.
Just keep in mind that whatever you buy, the seller has to ensure the product they sell is fit for service and of merchandisble quality. That is they must abide by your statuatory warranty within ACL. The manufacturer, in once sence, simply provides support to the seller via their manufacturers fixed duration warranty. Again, keep in mind that your ACL statuatory warranty right offers an undefined duration garantee as such and this can trump a manufacturers fixed warranty duration. As such, never put up with any dealer's out of warranty crap even where a manufacturer doesn't accept a claim as the seller can't fob you off to the manufactrer and thus decline a vaild statuatory warranty claim. After all, dealers being registered businesses are obliged to follow the law just as we are...
As a last point, all work provided by someone being paid for such work is also convered by ACL. So paying for some eplacement part only to find the fault still exists would be covered by ACL as a failed repair and should be refunded. Yet we vehicle owners seem to accept the situation where a dealer can continue to add parts hoping to find the final solution at out cost... odd indeed