I have a 2001 Dodge Dakota truck, 64K miles, has had a complete tune up…Problem is that the motor seems to “surge” at times…more when using cruise control but some also when not using cruise….Seems more often when going up a hill but at times on level road. The RPM will move from 1500 to 2000, or from 2000 to 2050, etc….I have had it at the Dodge dealership 3 times and they cannot find the problem…When they drive it, the problem doesn’t occur…You don’t feel it when driving around town but on a long trip you feel it off and on…Can you give me some insight as to what the problem could be?