I am not convinced about replacing the torque converter or valve body as a fix
Hit Redline and others have gone down that route to no avail .
Patrick Irish may , as he says , have reset the computer by having power disconnected for a time , others tell a similar story .
I have no idea , of course , how serious the issue is on your car but think back a week or so to where I said I also have slight hesitation but only when A/C is on .
I think these cars have , for want of a better expression , electronic tantrums sometimes .
maybe it`s bad signals caused by a bad connector .
a buddy of mine had issues with a ZF transmission on a VW going into failsafe mode and no one could find any problem .
I simply asked him some questions about the when and where it happens , turns out he drives through puddles whenever it rains so a clean up and grease up of some connectors and it`s good as new for a while but he won`t stop driving through puddles .
he drives high miles in his job so a few months later the problem is back .
anyhoo , just saying , cool yer jets and look at the simpler solutions before you spend a lot of cash .
good luck .