Overdrive quite working after computer restart

[T_Aggie03]

The day after I reset my computer, my Overdrive quite working. Is this just a qoincident, or did I do something stupid like not leave it disconnected long enough. I left it disconnected for 2 hours. Do you'all think I should leave it disconnected overnight and see what happens? It doesn't really make since that the computer would just reject overdrive because of a simple computer reset. HELP....

 

[kps36]

One question, what did you do/modify to your truck to make you want to reset the computer. And as far as your OD not working, does the light flash, stay on and can't get it off. What year and type tranny (auto I assume) and miles ? If it is a 94 or before auto with 70+K miles it may just be a coincidence and time to start saving for an A4LD rebuild.
Also check the modulator valve on the tranny. But I would think the tranny would be 'mis-behavin' at all shift points.
Does it run okay from 1-3 (or 4 if a 5spd auto) then just won't go into OD ?

 

[T_Aggie03]

kps36, I didn't do any modifications, I was getting bad gas mileage along with a rough idle. Someone on the forum told me to restart my computer and see if that helped any. It didn't.

To give you a better idea of what happened:

While driving at about 45 mph a weezing noise started to develop in what sounded like under the hood. This sound would continue only momentarily and ever since then the OD won't work. Since I own a '93 it doesn't have the O/D light, so there is no flashing light. At times I think it actually wants to kick into O/D because the transmission will "bump" when the RPM's reach the point where the transmission would normally shift into O/D. The "bump" isn't huge but it is noticeable, and doesn't happen all of the time. Do you think is something electronic or mechanical? You mentioned something about a modulator. Where is it located and how do I get access to it? Is it something I am capable of handling or is it "Mission Impossible"? One more question, I promise. I have to make about a 180 mile trip this weekend with no time to get it fixed before hand. Do you think it will further damage the tranny if I drive it?

 

[T_Aggie03]

kps36....I forgot to mention that it runs fine (besides the bump) through gears 1-3, it just won't shift into overdrive.

 

[914x4sport]

This happened to me after putting in my k&n filter and reset the battery, Have you tried just revving it up a ways from where your normal shift sped is, That seems to work for me,. Its like you have t o get the converter used to locking up after you reset it. I just accelerate to about 60 and sit there till it decides to reengage.After that no probs, Hope that helps.

 

[T_Aggie03]

Don't Understand

I am not quite sure what you are getting at, I am sorry. Are saying put it in park and rev it to about what? (3000,??) If you are saying drive it at 60 for awhile, I already did that. I drove about 360 miles at about 65 in D. I really dont know what the heck is going on. I had the vacum regulater replaced about a week before, so I dont know if this caused it or what?

 

[914x4sport]

DOH! It might be your regulator thats the problem,But the same thing happened to me on my last tranny(didnt kick in after driving 65 or so for a while_ and I ended up losing D which then led to complete A4LD Failure.Bring it to a shop and have them check that regulator... I believe that is what controls your o/d. not sure though. Anyway best wishes...

 

[T_Aggie03]

914x4sport, I replaced the regulater only weeks prior to the Overdrive failing. Maybe the dealer installed a falty Vaccum regulater. I plan on bringing it in on friday (tomorrow) and have them check the regulater, but how do I know they are not "Joshen" me and telling me that it is something else and not the vaccum regulater that they just replaced? I know you have to take off the exhaust to get to the vaccum regulater/modulator, but is there anyway I can just look to see if maybe it "popped" out? That would save me a trip to the dealer and it would also be a quick fix. Thanks alot.

 

[Rod Bivens]

This may be a longshot, but when was the last time you changed the transmission filter? The exact same thing happened to my 94 Ranger. My OD would work for part of a trip, then all of a sudden just not go into OD. All I had was D. I replaced the trans fluid and filter, and it has been fine for a couple years now.

The transmission had been torn apart for service by the dealer and I had just assumed that they had replaced it until I looked back at the parts list.