Thats about where im at right now with this thing. Little back story on it. its a 91 F250 with a 7.3L. I posted on here last week because the battery light was on. I had a 2 moth old alternator and voltge regulator in it. The truck drove and ran fine after i got it started, the last few days ive had to jump it. Today i finally got around to fixing it. Returned the alternator and voltage regulator and got new ones. Had to charge one of the batteries to get it started. Now the alternator is finally putting out 14.5 volts. BUT now when i drive it shifts in and out of gears. itll ****f fine all the way to OD but then itll down shift randomly the back into OD and it just keeps doing this. The transmission is less than 6 month old with maybe 2k miles on it. I have had this problem before right after i got the transmission done. Thats also when i first started having battery issues. This is when i replaced the alternator and regulator the first time and it fixed the problem. Now its happening again after i replaced the regulator today. so does it have something to do with that? The last time this happened i hit the old alternator with a hammer and it was fine for a couple days. whats going on?! Is it a wiring issue somewhere? Or did i get a bad regulator? Any help is appreciated!

 

Is your tach working? If the tach sensor is bad, it'll make the tranny shift funny.

 

Not too familiar with the e4od, but will the TPS also effect shifting....

 

MLPS will cause the tranny to hunt for gears, FORDF250HDXLT has a right up on almost everything for this trans, he'll have one for the MLPS and what issues it will cause

 

Here's a write up F250 did on adjusting the TPS.

Join Date: Jul 2006
Posts: 11,280

insert negative lead of multimeter into negative battery post.
select 20v DC.
insert positive lead of multimeter into bottom wire plug without disconnecting anything.
turn the key to RUN (engine off.) turn on meter to get aprox 5V DC.
if you don't get 5 volts,then repair this plug or the wire so you do,or all effort is worthless.

next insert positive lead of multimeter into center wire plug also without disconnecting anything.while leaving throttle linkage alone,and AFTER you already set your idle speed to 650-700 rpm (with the cold advance solenoid off,or unplugged for good measure if engine is cold) tweak your TPS so you get about 1.20 V
push your throttle linkage forward to WOT so you then get aprox 4 - 4.5 V. (i didn't snap a pic of that.oops.sorry.anyway mines a bit low actually.iv got 4.0V.i should work to see if i can bump this up a tad without effecting my idle reading some more.shifts great with 4 V though fyi.)
keep tweaking the TPS until both voltages are accurate...that's the tricky part.
while doing this with an unknown mile/old TPS,slowly push the throttle wide open,looking for any dead spots with your meter.if you find any,replace the TPS asap and adjust as needed again.........actually,you know what guys.this trans is far to expensive to mess around with.if you have an unknown aged TPS,do yourself a favor and just replace it.

if your still having issues,be sure to set your meter for OHMS.
turn the key OFF (for safety of your meter) and inspect resistance between negative terminal and the top wire plug pin.repair wire if your getting too much resistance.ideally,you want 0 ohm's.i didn't test mine,so i don't know what's common.very little if anything to account for wire length...maybe,but if you clearly see high resistance,repair the wire so you have a good clean ground to your TPS.
the article didn't specify readings,they clearly skipped that and left ?? for "voltage" which is also inaccurate no less.it's like someone didn't get a chance to finish the test and they left it out lol.but you want very low,if any resistance reading there anyway.i didn't bother because my trans downshifts and upsifts flawlessly.had i an issue,i would test the ground wire.pretty basic anyway.

you must work on repairing your wires id say linus.sounds like the pcm isn't getting enough voltage,or the wires from the pcm to the tps are corroded.you've got bad/old dirty wiring there someplace.
and of course,you can't have any missing TPS screws.the two mounting screws and the two adjustment screws are vital.replace asap.

iv kinda been thinking about building my whole E40D harness myself with tinned marine grade wire with all new plugs,but since everything seems ok for me still (hard to image with a 19 yr old truck though really?) that i haven't bothered yet.
anyway,make sure you have good wires for this trans,or you'll be fighting gremlins from now until a zf5 swap.
when all working correctly,a zf5 truck with all things equal,couldn't touch you off the line from 0-60.

i wouldn't drive the truck in its current state linus,because it could cost you an engine and or trans.....though most likely over some time.it's not healthy for sure.

 

WTH does "blow it in place" mean?

 

Check to make sure your third brake light is working (if you've got one -- not sure on a 91). If it's out the E4OD will act crazy.

 

Pile explosives around it, walk away, and boom?