My BF (06) XR6T ute has been playing up on cruise control. It is a 6 speed auto box with 110000km's. I have found when cruise control is on, or when driving without cruise control but when engine under load (going up a slight hill), the revs bounce up and down between 1500 & 1700 rpm and sounds like the car is surging. Was also getting the same shudder that a manual car gets when in a gear too high and going to slow. I took it to the transmission place to get a service and when dropped the pan basically the oil was water. Found the heat exchanger had sh*t itself and contaminated the oil with coolant. Basically rebuilt the auto (converter, clutch, plates etc...). The reco has fixed the shuddering problem but the surging still exists. I have today replaced the throttle position sensor and still have the same problem. Does anyone know what may be causing this. Over the last couple years I have been getting my ETC light come on and off randomly on the dash hence why I changed the TPS. The transmission guys have also managed to data log the ecu when driving and picked up the codes relating to the pedal position sensor, P2127, P2129, P2138 & P2140. Will this somehow effect the yo yoing of the rpm when the engine is under slight load (going up a hill with cruise on or off)? Thanks for any input!