I have a 2008 hhr automatic and when im crusing at a steady 35-40mph the rpm gauge starts bouncing and then the car starts rocking back and forth, no service lights come on, the car has 21k does anyone have any idea what it is.
Thanks

 

Can you explain the rocking back and forth further?

 

mine does something simular. it acs like it cant decide what gear to stay in.

 

back and forth means that it dosent know what gear to stay in

 

we had that same problem with Sara's car... it would do it at parking lot speeds too and just stall... after 5 or 6 trips to the dealer they finally replaced the whole fuel rail (injectors and all) and it hasn't done it since.

 

up to what mileage do u need to have to get all that replaced