I have a 2004 Saturn Vue with the a 3.5L V6 that the RPMs slightly jumps between 20 to 60 MPH. Though if I place the vehicle on cruise anything over 50 MPH the RPMs stay steady (still very slight jumping occurs with cruise around 20 - 40 MPH). The car runs great and I just got it out of the shop with a full diagnostic and everything came back in really good shape. There is no jerking motion with the RPM jumps so I don’t believe it is the transmission itself. From the research I have done I’ve come up with a few possibilities:
- Idle Stabilisation Valve
- Throttle Issue
- Throttle Position Sensor
- ERG Valve
Please let me know if one of these makes sense and should fix the problem or if you can think of any other issues.