leaking injector? or bad?

[HANK1948]

Iam thinking that I have a leaky injector, my truck starts alittle hard and when Iam cruising down the hyway at 70 or more and let off the pedal it surges but wont do it 65 and under it also sounds too smooth at idle like all the cylinders arent firing, also if I try to start it without pressing the pedal down 1/2 way it will idle very rough like all the cylinders arent lit untill I take it out on the road and floor it and there will be a bunch of smoke and then it seems a couple of cylinders come to life and she takes off and runs good any body got a clue?

[john8662]

Do the usual first, I suggest changing the fuel filter. You've got the easy one to change if you're working on the 88 with the Model 80 fuel filter cartridge.