Hi there, curious if anyone else has noticed this.

At times, my 5.3l Silverado when it revs in neutral seems to do so "choppy"(at like 1000 -2000 rpm). Like when looking at the tach, it seems to hesistate at points and then rev smoothly from there after.

I have no codes, drives absolutely fine. And at other times, it will rev up perfectly normal, nice and smooth.

Any thoughts if this is a problem, bad module or control? Or is the engine trying to limit or adjust itself and I am just seeing the effects since I am playing with it?

Thanks for the comments

 

I've posted the exact topic before not too long ago. Same range, 1000-2000rpm, usually around the 1200rpm range. I've noticed this from the start and only had the truck for 5 months. I believe this is the truck coming out of V4 and going back into V8 during acceleration. Other people said the same on my thread and watching the rpms today as I was driving I noticed this happens when it goes back into V8. I'm certain it's the active fuel management. If you have DIC, put it on the economy mode where it tells you your mpg and you'll see. I noticed it slightly with my stock exhaust but when I switched to a dual flowmaster exhaust it became much more audible. Now I hear not only when it goes from V4 to V8, but when I'm cruising in V4 it does it the entire time just a bit lower. Does it also vibrate the gas pedal a bit?

 

Rereading your post you said it does this in neutral, does it do it when you're driving? I haven't noticed if mine does it in neutral but that wouldn't be active fuel management. I'll have to try that out on my truck.