Watch your tach, will show a slow down or increase when it lock or unlocks. My 02 shows 200-300 RPM change. Open road with slight incline will reflect the change easiest. Once you are used to the feel of the lock-up you will notice it at other times also.

 

Perhaps does it feel like it is a misfire. Never really toke notice of rpm change but will take it back out for a drive this evening to check. Also need to pull my codes from todays 50 mile round trip to work. Will be checking in alittle later to post my findings. I appreciate the help!!!

 

I guess it could be interpreted as a miss fire, its more suttle (spelling) then a gear change but more than an AC cycling bump.

 

Toke it for another drive this evening and noticed now that the torque converter (As you mentioned) does lock and release when it shouldnt. I was expecting to feel this more while into the gas than off. What I did notice is that when I would release my foot off the gas at 55mph the rpms would slowly decrease then drop suddenly from around 1500 rpms to 1000 after hesitating alittle, then drop again to 700, then jump back up to 1000 again. When I say drop, I mean it doesnt slowly decrease the way it should.

Rechecked the codes again and the only one that comes up now is the 628 torque converter. The 634 MLP went away. Odd enough.
I looked up the Manual Lever Position Sensor in my haynes book and it mentioned that it could need ajustment inorder to work the torque converter properly. Some reason they show and mention needing a special Ford tool (T89T-70010-J) inorder to do this adjusting.

Could the MLP be in need of adjustment even if the code isnt present at this moment?
The 634 code must have come up for a reason even though it went back away for the time being. As I mentioned earlier, I had this 628 code before, along with the 452 VSS. Once I replaced the VSS, it corrected the 628 and the truck ran fine.

Honestly, Have no idea on how to even begin an adjustment other than what the Haynes book mentions, which is very little.

 

It is possible you won't get the MLP code with it out of adjustment. It can still be working, but not relaying the correct gear the truck is in.

 

I tried to look up on how to adjust the MLP but nothing is mentioned. How would not being in the selected gear ratio cause the torque converter to jump in and out the way it does?

A friend mentioned that he heard that all there is to adjustment is to losen the two mounting bolts and aline the two marks (One on the shaft washer to the one on the MLP housing surrounding the shaft). Does this sound somewhat correct?
I cant see how the two marks would have shifted out of line if the MLP housing is bolted tight, unless moved by a sevice center while being serviced.

How does a properly working torque converter improve performance? My truck hasnt been picking up speed as it was a month or so ago. Push in on the gas and slowly pick up speed. Especially on the highway.