When I have a half tank of gas I have a hard time getting up to highway speeds, but when I fill up the gas it doesn't have a hard time. Is this just something that most civics do or do you think that this is an issue? I have a DX and D17a2 engine.

 

That is a very unusual problem, I think, but if there’s debris or sediment in the fuel tank, it might mix with the fuel more when the tank is low, affecting engine performance. A full tank might reduce the likelihood of this happening.