First I must appoligise, I only seem to come here when I have a problem, and today is no exception. My wife went for a trip in the AWD 91 and was happily going along for some 150 km, stopped at some lights and lost drive, I arrived some 30 minutes later in time for the trans to cool down, it felt like it shifted into drive but then felt like it was slipping to such an extent it would bearly move the van, so I shoved in trans fluid and no change, then I tried all gears and the same in all gears, then in 1 I revved it hard and it locked, without delay I pulled into the nearest car park and when looking for a spot to park up the van I felt it was fine, 2 and 3 were also working now, but in DO (overdrive) it was jsut slipping again, I tried R and again it was locking up and felt fine, my wife got back in and drove it home in 3, again no slipping on steep hills, as soon as DO was selected it slips, now to mind mind it was the overdrive unit, however on a quick search I found someone posting a similar problem with this reply. Does this sound about right??
On another note, I jsut brought a nice 95 AWD for the grand sum of $200, it needed a new screen, a bush in a upper A arm, and a safty. So hopefully I will have some time to fix the first one. As usual any advice is welcome.

"On a 90 model, I doubt the transmission is TOTALLY controlled by the PCM,unlike newer models that have shift & pressure solenoids that are controlled by the PCM. In your case,the only PCM controlled functions would be overdive and lock-up,so you should still have reverse,1,2&3. I'd remove the pan for a fluid/filter change and also to inspect the internals of the trans. For your overrich condition, I would suspect either the fuel pressure regulator or the MAP sensor. As an added precaution,you should change the fuel filter because a partially or badly restricted fuel filter causes the PCM to widen the injector pulse in an attempt to enrichen the engine after the O2 sensor tells it there is a lean condition.The lean condition is a result of simply low fuel pressure, but the PCM doesn't know that,it just keeps widening the injectors and you end up with a rich condition.
Phillip"

 

I assume you mean OD (Over Drive) and not DO (or maybe you do, Dumb Overdrive?)

I would crawl under and check out the solinoids on the side of the tranny. One controls the OD, and I think it was cowgirlmechanic that had an issue with her wire harness burning up there. Once replaced everything has been fine, (at far as I know.)

At first from reading your description I thought that your Torque converter went out. But sense you have 1-3, I would say that it is the solinoid, wiring, or your OD lockup.

BTW the only trannies controlled by the PCM are the '96/'97 4r44e and '97 5r55e

And sense you feel bad about just asking for help, you can go ahead and reply on my thread here: https://www.ford-trucks.com/forums/s...d.php?t=390160

 

Did the engine overheat or did the transX blow fluid out?
What does the transmission fluid look and smell like, is it a bright clean red or some other color? Compare odor to new trans. fluid, should be no burned odor and same color.
Aero. auto trans. are tempermental on trans. fluid level, only measure parked on flat surface with engine/trans at normal operating tem. Overfull causes foaming, overheating and slipage. Never run with no fluid showing on dip stick.
How long since last transX fluid and filter change? Any leakage on transmission or cooler lines?

 

No overheating, new oil when I rebuilt the oil pump and front seal on the transmission, level looked alright but I threw some more in just incase, the van was pulled on the side of the road and with no drive I wasn't going to push it to level ground, the oil looked like new, no trail of fluid like when the seal blew, dry underneith. The box seems to work fine in R 123, just not in overdrive, I'll get to looking at the solenoid (no idea what I'm looking for but I'll look just the same. when you put it in overdrive it seems to select the gear but there's not enough grip to pull the van along, all was perfect before it happened and I thought either the OD unit has gone or there is some controller thast was not allowing lock up. I'll hopefully get back to you and it will be a simple fix, in the mean time anyone have a pic of the solenoid and it's location, it might also be worth mentioning at this point that 9 months ago I found that the AWD module was missing, when replaced the light flashed so I bypassed the module with a switch for AWD on demand, I know this is probably unrelated as it concerns the lock up of the front and it still has AWD in 123, infact everything except the overdrive still performs adequatley, however without the overdrive the 130km trip to and from work will work out expensive.

 

They are located near the modulator on the tranny. They look like round flying saudcers, I wish I had a pic, but I don't.

 

OK I took the van out today,now I rang a transmission guy who said it would probably need pulling down to look at and wanted (sit down for this) $1800, i I thought what the heck I'll just use it with the 3 gears afforded in D, while driving I poped it into OD, the thing worked, pulled up at a stop sign and it wouldnt pull away, into D and everything OK, next stop sign pulled away in OD. Now everything seems fine again, it works as it always did??? now I know mechanical faults don't just heal themselves but what gives?, I'm guessing some minor ailement that a good oil change will sort out.
Any ideas as always are welcome.

 

WOA, $1,800, to R&R an A4LD? This guy must rebuild em out of gold.

Around here I can get a fully rebuilt A4LD tranny w/ TQ converter with 3yr/36k mi warranty for around $700 + core. For a DIYer, you are looking at a weekend to pull and replace. A Pro should be able to do it in about 3 hours.

I would talk to some other places if you don't have the time or space to do it.