Replaced O2 sensor, had computer reprogrammed and the check engine light is still on.

I Wasn't able to find any information on this but I remember finding a lot of articles and posts pertaining to the Astra and a certain code that causes the check engine light to come on. What ever the cause of this particular code, the light has reportedly for some reason wont go away. Look through google and see if you can find a TSB (Technical Service Bulletin) as I remember seeing one for this problem. I wish I could find the links for you. Either way, most of the time the check engine light comes on when there's a problem with some emissions system and more often than not means absolutely nothing with respect to the driveability of the car. If I were you I wouldn't waste too much money on it unless the car starts driving differently. The only problem with this is that if something ELSE goes wrong, you wont know because the light is already on. Personally, every car Ive owned, I modify and put performance air intakes and exhaust on the cars. The check engine light will generally come on and stay on forever because of this and Ive never had any resulting problems from it. Just something to consider if you don't have a ton of money to throw at this problem.

I dont want you to under estimate a check engine light as in some cases it can be a serious problem. I just want to put it out there that a lot of people blow the Check engine light WAAAY out of proportion when a lot of times it's nothing dire. You could try taking to a couple different dealers to see if they have had a similar problem and WERE successful in fixing it. Just be aware that in situations like this where the problem cant be solved, shady dealers will either keep throwing random parts at it and the repair bill will get out of control, or they will turn the light off altogether just to get you out of there so if there's ever a real problem you wont know because they killed the light entirely. Just don't get angry and yell at dealer because that will never help you in this scenario. they'll be more likely to do what it takes to get you away from them even if they do something shady