i have a 92 laredo, it has the 4.0 and the aw4. i know the torque converter is supposed to lock around 40, and its not.

it tries to every once in a while, i can feel and hear the rpm drop, but it opens right back up. i do have to commute pretty damn far on a high way, and i know im loosing lots of mpg because of it. i wanna know if theres a wire that controls the torque converter, if so what one. where are the plugs and is it possible to unplug/clean them. i can brush the contacts with isopropal alcohol to clean it up...i just need to know where they are...if thats not it, what else could cause it to not lock?
oh, and when it does lock, if i hit a bump in the road, it will unlock...thats what makes me think its a wire/connector.

nobody has any ideas?

According to the FSM, it's either a valve body issue or a TCM issue.

Locking torque converters are controlled hydraulically, ie. it is fluid pressure via a solenoid valve inside the transmission that sends high pressure fliud into the conveter clutch to hold it in the locked position as required. It won't be a matter of just repairing a wiring harness, it is more likely going to be dirty or clogged passages in the valve body of the transmission. you may have some luck with a transmission flush, but sometimes those cause more harm than good. Good luck,


Corey

thanks guys. ill have to research it some more...maybe take it to a shop