1991 Chevy Caprice chugging

U guys told me it may be my egr valve it was wierd after u told me that my car ran fine all of a sudden but then just the otehr day it started chugging again but this time it was worse it chugged as long as I had my foot on the gas when I let off it would shake but thats it they I would go to go up a hill and put the gas down alittle further then it would almost backfire but not a loud exhaust backfire it was wierd then I would hit the brakes and it would die all of a sudden start up np at all I dont know what to do, the car just doesnt sound or run the same as it did and I also noticed with my throttle body injection that when I pull the air filter off there was gas on the filter cause the injectors r right ther so I dunno