Every time i gently put my foot on the petal it takes about 5 seconds until the RPM is as high as 4000-7000 and I can only be driving 25mph. Why?

 

Because ur K swap is too powerful.

 

by any chance can it be the throttle position sensor?

 

Well considering you gave us absolutely no information on what model or year you are having an issue with?????

First thing to check would be your throttle cable for proper tension and smooth operation. Then you can start looking at electronics.

Once we know what year your car is, there are a couple different ways to check other things.

 

2000 honda accord lx 4cylinder

 

In that case check your throttle cable. If that is ok, hook her up to a scan tool and che k the live data for TPS response. While it's hooked up, if the TPS checks out ok, you can monitor other sensors. I.E. engine coolant temp.

Is your check engine light on?