Join Date: Sep 2006
Car: Rover 75 CDT Club Auto
Sorry to hear that, but I am very suspicious of that diagnosis. If the torque converter was cracked then you would be getting higher engine revs most of the time ( ie it is slipping more than normal), but it would change gear. Gear changes are effected by a separate hydraulic pump, which is controlled by solenoid valves, which in turn are controlled by the ECU. If the hydraulic pump was knackered then yes that would cause major problems. Also a misbehaving ECU could cause similar problems. There is clearly a pressure problem, which the ECU is trying to overcome, or a pressure sensor is wrong, which affects how the ECU behaves.
By they way, you have not said how many miles the car has done? If it has done a lot, with no oil change, then yes, things could go wrong.
I personally would get a second opinion, preferably from an EX Rover service centre, and put it on the "T4" diagnostic set.