lockup tourque converter

[twfs]

Hi I have a 91 f250 with 7.3 with e40d transmission. I recently replaced the the throttle posistion sensor because it was shifting hard but now when it shifts to 3rd it almost immeaditly locksup the tourque converter where the truck would probably fall on its face under a load because the rpms really drop. Before I never even noticed that it had a lock up converter with the old tps in it. I adjust it to what I had read on a previous post wich was what told me what was wrong in the first place. 1.158 volts at an idle and 4.28 wide open wich I figured that was close enough to the 1.2 and the 4.5 that was posted. Any ideas on what could be causing it to do that or is that normal. Any help would be greatly appreciated. Thanks

[archangel]

Originally Posted by twfs

where the truck would probably fall on its face under a load because the rpms really drop

Sounds like it's going into 4th and skipping third all together if it's falling on it's face and dropping a bunch of rpm's.

The converter locking up can be mistaken for a gear shift by some but I do believe it does lock up under full throttle at any rpm as long as it's above first gear.

[twfs]

Hi thanks for responding. It shifts 4 times just when it hits third it locks it up almost immeaditly. Like I said it never did it with the old tps just with the new one. So that was making me wonder if something else is wrong

[ford trans tech]

you most likely have the fipl/tp adjusted too low rotate it slightly clockwise viewing from the drivers side to increase the throttle signal too shift later
the torque converter will apply in all gears anytime wide open throttle is commanded
also setting it by voltage reading at idle is not the preferred method and will not always have satisfactory results , the correct method is with a gauge block and a scan tool
it is adjusted at half throttle , the reason is due to varying geometry between the fipl and the actuator on the injection pump

[twfs]

Hi Thanks for responding. Went on ahead and got another new tps and put it on this morning considering how everything was fine before other than the hard shifting and set it like I had the other one and seems to work alot better. I don't have access to the things you mentioned to properly set it. Where could a guy get the stuff you mentioned to set it with and is it very expensive. It goes ahead if I am just probably 1/4 of throttle or less when it shifts to 3rd it won't lockup for a few seconds wich I like a whole lot better and at full throttle it shifts right before the yellow on the tach. Do you think this is set close enugh not to worry about. Thanks again really appreciate it.

[ford trans tech]

i really cant say without actually driving the truck but set it to where you like it
it can be done by trial and error by making small adjustments and road testing it
to set it the factory way you would need a scan tool that has an audible output tone
a beeper built into it and you can substitute a bolt with a 13 mm head in place of teh gauge block , teh factory gauge block is .515 thick the 13mm is close enough
you performed a key on engine off test the scanner will read out the codes and also beep out teh codes when ithas beeped out the last code depress and hold the o/d cancel button a few seconds and the processor will enter teh fipl adjusment phase it will begine beeping slow beeps when it is below adjustment and fast beeps when its above teh adjustment then will have a constant tone when adjusted properly with the gauge block mounted between the wide open throttle stop screw and the lug it would contact on the pump