My 93 GMC Sonoma 2.8l v6 is running odd. At the rpm range of about 1,500 to about 2,500 it acts like its hesitating or not getting gas. while driving down the road in those rpm ranges it starts the lunge as if the engine is being lugged i have replaced the fuel filter and just cleaned the tbi system on it. the fuel pump has been replaced about 4 years ago. any help will be greatly appreciated.