Transmission lockup

[502BBC]

my converter is locking and unlocking when I am driving giving me a missing feeling, I unplugged the 4 pin connector and it went away, is this caused by the converter or the ECM going bad?

 

[HOTTOGO]

I would start with..

checking the tcc solenoid (easy fix if that is it). Here is an article that should help, or do a search on here of the old posts it will be covered in the past posts.
http://www.montecarloss.com/TCC_Solenoid.html