99 Taurus Transmission mystery

[skiboyne]

Hi, I have a 99 Ford Taurus with the 3.0 and a 3 speed automatic with o/d. When it's cold, then for about 20 minutes after initial startup the transmission shifts perfectly. After a run on the highway (when it's good and warmed up) From a complete stop it slips and then shifts, slips again then slams into gear. This is during the shift from 1st to 2nd and all happens very quickly. After that 1 to 2 shift all other gears shift in and out perfectly. However the 1st to 2nd problem will happen consistantly untill the car gets a good rest 2-3 hours, then its back to no sign of the problem till its warm again. Also when it's doing the slip shift thing, if you take it up manually through the gears, no problems. I had it to a tranny shop that I've used many times and know to be a good one. They searched for 3 days and couldn't find the problem, and it has no trouble codes. Eventually they ended up putting in a used transmission for me, same exact problem. Does anyone have an idea or heard of this before?? thanks

[GPFred]

I had an 87 Taurus wagon that did the same thing. It was a pretty standard situation for the Taurus then. Never had it go totally and never did a thing about it. It almost sounds like some kind of sensor as you say that when you shift manually, it shifts fine. ANd the same occurs with the used tranny that was put in. Just a hunch and I'm sure the tranny shop thought of that. Sorry I have nothing more to offer. Good Luck.

[Millermagic]

I'm assuming you have the Vulcan engine - 3.0 ohv? I think your transaxle is done though.

[skiboyne]

yeah, I have the vulcan. I ended up selling the car I hope the next person has fun trying to figure it out., They were under the assumption that it only needed a tranny.

[weekendmac]

Did you ever solve your mystery? I have a similar situation.

[skiboyne]

I never did figure out what it was, I opted to sell the car. The transmission shop was positive it wasn't the transmission, rather something telling the transmission to do what it was doing. They replaced the transmission with a used one and had the exact same problem. Everyones best guess was the computer. Not that expensive of a part to try if all else fails.

[kjvw10]

Originally Posted by skiboyne

I never did figure out what it was, I opted to sell the car. The transmission shop was positive it wasn't the transmission, rather something telling the transmission to do what it was doing. They replaced the transmission with a used one and had the exact same problem. Everyones best guess was the computer. Not that expensive of a part to try if all else fails.

If it is the ECU the real cost involved will be the reprogramming the key at the Dealership / locksmith. The throttle position sensor could actually be the key to this. I have a 2000 ford taurus did this, I did a tranny rebuild end to end. Found out that the trottle position sensor was sending garbage signals to the computer when it was warm. So the tranny thought I was pushing the throttle at the wrong rate. Hope this helps someone. Electrical parts are normally non-returnable so make sure you are sure before you swap them.