Needs some help
 

So this is the issue. I have a 2002 f4i- about 7000 miles. It runs strong and has power. But when im just crusin at a steady speed and the rpms are around 3 to 4 thousand the rpm tends to surges .Not sure what it might be thought. ive check the ecm and theres no codes. I know that it did sit for a couple years. Ive ran about 15 or more tanks of gas through it. Id just like for it to run smoother around them rpms
Any advice!!!
Preston
Pschuma0@email.cpcc.edu