Here recently my 03 GT has been sputtering, bad. Press the pedal down and it doesn't increase in power at all. There are so many theories that people have given me that I am at a loss. Everything from the ignition coils to injectors. Next on my list to try to weed out my problem are the coils. Does anyone on here have a preference on brand or where they got it from? Advance was wanting over $100 for just one coil and it wasn't even Denso made. Any help is appreciated!
You shouldn't throw parts at a problem like that without doing some diagnosing first.
Ignition coils will throw a CEL if they have problems, you can also easily test them by sticking a spark plug into the end while it's out of the engine.
Recommend checking/cleaning:
Air filter
Throttle body
MAF sensor
Vacuum leak at the intake gasket
Do you literally mean that there is no change in power with the accelerator? Does the car move at anything more than idle speed?