2001 Dodge Dakota Initial hesitation and engine flutter

Backing out of my garage in the morning I get a pretty good thud when the tranmission engages. It feels as tough there is slack that is being taken up before the transmission engages and moves the vehicle. All u-joints and shafts feel tight. Is there any way to test this through diagnostics, i.E, is there a code saved to the on board computer? If so, how do I read it?

Also, the RPM of the engine seems to flutter at road speed. It seems to happen more before the vehicle has reached full operating temperture and / or closed loop operation. The RPMs will jump 500 - 1000 without warning. I have replaced the cam position sensor with little to no improvement. Again, is there any way to test this through diagnostics, i.E, is there a code saved to the on board computer? If so, how do I read it?

Thanks a lot