engine missing/hesitating

Hi, my Daughter just bought this 1997 Grand Am, with 76,000 miles on it. The car runs great, except for a miss when the RPM's are under 2 and you are doing a slight acceleration up a grade or hill. Once the car shifts and the RPM's go over 2, the problem is not there. She bought the car with 3/4 of a tank of gas, ran it down, filled it up, and then the trouble began. We ran that tank down, thinking it was maybe the gas?? then added fuel inj cleaner/dry gas, and added 12 gallons of gas. The car is now almost empty again, and still missing......does anyone have any ideas here? Should we give it more time, add something else, or take it somewhere? Does any place do diag's for free?
thanks

first off what engine is in the vehicle 6 cyl or 4 cyl.you can tell by the 8th digit of the vin #. also the free diag thing if you go to the doctor does he tell you whats wrong for free. be more specific and i'll try to help you out.

I believe it is a 4 cyl, 2.4_liter_MFI_LAN, the 8th digit is a "T"
I know nothing is free, I just thought I would ask :rolleyes:
Thanks for your help

that engine is very vulnerable to injector clogging try running somemore good injector cleaner through it and see if it clears up if not the injector at fault will have to be replaced.also that engine has an integrated ignition system thats under the cover on top of the engine. the coil housings are known to get carbon tracked but usually it will backfire or only run on 2 cylinders or not start at all when this happens.you can take it to a shop that uses a bg injection cleaner it's about the strongest and most effective i've ever used.

thank you for the info, we just filled the gas tank up again, so I will have to wait until the next fill to add some more inj cleaner. We will see what happens, maybe the other stuff is still working to clean it up?? Thanks and I will let you know how it is going here.

GM has a recomended injector cleaning procedure which will work to clean your injectors! I do not reccomend any non GM cleaners as most don't work. GM TEC is the best cleaner to use.

I am familiar with the BG process and that one is a close second in its ability to clean the injectors.