Recently noticed a problem with my RPM’s fluctuating by a couple hundred when h9olding the pedal steady at 40 to 45mph, right under 1500 RPM. It feels like it would if you were slightly pumping the gas pedal. –not so much a stutter. It’s a 2005 Yukon Denali 6l. I have cleaned the throttle body but it hasn’t helped the issue. (though it did help the reaction time). I have a RAM air and predator tune since 06, but this recently started happening. Any suggestions or past experiences with this would be an awesome help!! Thanks!!!!