2002 vw gti has no pick up unless it is floored dont know what to do

trouble codes?

fuel filter?

sludge in oil from lack of oil change?

i dunno either!

Need a little more of a discription then that. As suggested above. Scan it for codes. It could be a number of things. It could be sludge in the PCV system (which is common for reasons listed above) could be a cat, could be that you haven't changed the plugs in forever. There are a number of things.