While driving the 2005 buick will sputter like its not getting gas and will cut off

Check the fuel rail pressure. It could be the fuel regulator.

I think you should go for manual first after that it would be easy for you to solve your problem. I had visited this site past 2 months before for my vehicle and find it quite helpful may be you will also get something useful here
Buick Allure LaCrosse Workshop Service Repair Manual 2005 2006 2007 2008...

sounds like fuel filter or screen on fuel pump plugged

Sounds like you have a injector leaking you can try looking at each one when you crank it and you may be able to spot the leak.

It sounds like you got a tank of bad gas. Get 4 bottles of dry gas and pour them into the tank and then drive it for a few miles. That works on many like yours. J.

change your fuel filter and check the fuel pressure on the fuel pump you may have gotten some bad fuel try some STP gas treatment make sure you have a half tank of gas and add a little more go somewhere you can drive 55MPH give these websites a try www.alldatadiy.com and www.autozone.com wish you the best of luck Michigan Man.

Sounds like it could possibly be a vaccume problem, the computer sees that the vaccume has a low pressure and thus fludding the engine, or visa versa, it's seeing too high of a pressure and cutting the fuel comsumption to a minumum enough to make the engine sputter and die.. Does this happen when the cars in Netural or Reverse or Park? Just Drive?

what trouble codes do u have in memory please, need these to find root cause of this shut off problem.

could be the O2 sensors

has the fuel filter been changed? this sounds like low fuel pressure due to a partially clogged filter or defective fuel pump..