1993 Grand Prix Le 3.4 DOHC
Just purchased for real cheap to get around back and forth from work always been a pontiac fan but this ones got me baffled. got it home changed plugs cleaned injecters because it was definetly not right this seemed to smooth it out. still at take off seemed to miss or surge a bit but ran real smooth around town. problem i seem to have now is that when i get it on the highway at speeds above 55 and the engine idles back it i can feel a real definite surge but goes away when i accelerate then comes back as it idles back to cruising speed. The check engine light comes on at this point but only here, around town it does not. Any ideas or directions i can go in?

Could be the Mass Airflow Sensor...when mine went out, the car felt like it was misfiring sometimes, and the SES light would come on. You need to find out what code it's throwing to turn the SES light on, that will narrow things down a lot.