i notice somtimes when taking my car out of reverse or sitting there with the clutch in that the rpms will drop low, rise, drop, rise,etc, it will go up and down like 3-4 times. sometimes it will drop so low for a moment i get a bit of an engine shake like the car might wanna stall. i was just wondering what the problem might be. thanks

 

happens to me too and my car is stock its been happening since i got it brand new off the lot i dont know what it is either

 

When I got my GM stage 2 installed the reflash fixed this.

 

it happends to all of them. 2.0, 2.2 and the 2.4. Happends right off the lot. Its a defect i believe. A reflash will fix

 

I've also been experiencing this problem and have read on here that they do have a reflash to fix the problem.