Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
When you say you had injectors checked, does that mean balance rates were obtained and recorded? If so, can you upload those records so we can determine what's wrong?
On the other hand, if that hasn't been done (or the check was performed by an unqualified tech who did not use a Tech-II or equivalent scan tool), my suggestion is to get that done first as it will most likely reveal the cause of the leak.