Getting code 628 excessive converter clutch slippage. I have a new torque converter and a rebuilt tranny. I took it back to the tranny shop they checked it out. They said the only thing they could find was a engine coolant temp fault. So I replaced the ect and I'm still getting this code. I checked voltage from ecm to the ect I got 4.62v according to my Haynes manual it should be aprox. 5v is this in an acceptable range? Dose anybody have any other ideas of what would cause this before I go back to the tranny shop? I appreciate any and all input.