I have a 2000 GMC Yukon with a 5.3L engine. When I am driving around and the vehicle, it hesitates when in the RPM range of 1000 to 1500. It runs fine outside this range. It has been doing this this for a couple of months and bothers me sufficiently now that need to figure it out. What could cause this?
Try some choke cleaner sprayed on the throttle plate on both sides. They gum up with oil and such. That may cure it. If it doesn't check your fuel pressure it should be 60-66 psi and change the fuel filter.