Thump when slowing down

[Trophy885]

Hi Guys and Gals,
my apologies for being wrapped up in my little world almost exclusively of late.

My 3.7 FL 40v has developed a thump coming from the trans when slowing down normally, I also seem to have fluctuating tickover.
I have read somehere that the thump is caused by the MAF sensor, is this correct? Something to do with it sending the wrong signal to the Torque Converter?
Could any of you Gurus out there shed some light on this? As I won't drive the car until I have effected a cure.

Thanks in anticipation,
Steve