I don't get it to that extreme. What i do get is it fluctuating about 100 RPMs. First time i saw that it tripped me out. I got used to it now and it really just does it in the mornings.
2013 5.0, 6 speed manual, Brembo Pckg, 3.73 gears, American Thunder 40 series Flowmasters, 1 inch Lowering springs from Roush, J&M LCA, J&M Adj.Panhard bar, 20% Tint all around.