Any ideas on what might be causing the car to hesitate on
acceleration and changing gears? This is an automatic 4 cyl.

At times it feels like you need a lead weight on the gas pedal
to get it to accelerate. It hesitates at each gear change, then
sort of thumps into the next gear.

The "transfer duty solenoid valve" was replaced, which I
was told would fix this.

But it seems the same and now when it changes gear sometimes
it feels like there is an extra burst of acceleration without
giving it any more gas. It feels like when cruise control takes
over on a hill and causes the car to accelerate.

Thanks

Bill