i put a ls swap in my civic and had it runnin good but sometimes at low rmps it will studdered and just drop down and down and up and downwat could this be a cause of. ANd also it does not have a lot of top end power at all nemore what the hell help neone?

 

check ur plugs wires cap rotor and fuel filter

 

ill start with it neone else?

 

Sounds like ignition to me. Plugs, wires, cap, rotor, coil.

 

ok so if i slowly rev it up no spudder but if i just kinda slam on the gas up to like 3 or 4 it will spudder in between like 1 and 3 but after that no spudder