2000 Infiniti I30 hesitation after change of starter

I changed the starter on 2000 Infiniti I30. put all the wires and things back together and now when you push the accelerator more than halfway down the car bogs down. So i changed the plugs only the wires are in good shape and coils cost to much. replaced the plugs with bosch. the car runs a lil better but when you get more than halfway on the accelerator or try to go over 40 mph the car hesitates really bad. I'm very frustrated and don't want to goto infiniti. The was a check engine light that came on when i disconnected the maf sensor plug while the car was running just to see if it'd respond. I took battery cables off to clear the code. The check engine light was on before i changed the starter, but never had the code pulled. I've checked the vacuum hoses, made sure the air filter was snug and put plugs in right with diaelectric grease. whats next. currently the car is at a friends shop and he's supposed to have a guy that works at nissan scan it but it's been there 3 days. Should i go ahead and replace the maf sensor, i've tried cleaning it and that didn't work. when i drove it to the shape i dropped the trans in 3 to gain power and back to d and got it up to 60. but car hesistates at 40 and when i push pedal down halfway what is the best thing to do i know its not cost efficient to just replace parts, but the plugs were the same ones that came with the car. would the bosch plugs mess up the car