2001 Jimmy Hestation

Help I need advice. My check engine light went on some time ago. The code stated that it needed a tune up. That was done. However, since then it started acting up. It hestates between 1500rpm -2000 rpm's unless I accelarate quickly and bypass to at least 3000rpm's. But this scenerio changes also after driving around for at least 15 to 20 minutes and then the hesitation stops. I did run fuel injector cleaner and it resolved it for about a day. Any thoughts!!!??? Thank you

OK lets get something straight..there is no code that states you need a tune-up!
What you may have had was a P0300 misfire code.You need to have the cause of the misfire diagnosed and repaired.