I am new to the forum, hoping someone here has some experience that will help me, my 96 STS is not shifting into 3rd.

Under a hard acceleration, it stays in 2nd- doesn't slip or anything- just stays in second. Under normal driving conditions, it shifts out of 2nd and into neutral.

It throws no codes at all.

Tonight, we checked the A & B solenoids- removed them and they bench tested good. Tranny was very clean- no abnormal wear, no burnt fluid, no heavy metal, everything looked perfect.

Also checked the continuity of solenoid wires up to computer- wires were good.

Thinking to just change the solenoids anyways- just to see if that helps...but wanted some input.

Any ideas, advice, personal experiences?

Thanks in advance!
wendy

My first thought would have been the solenoid.

By any chance did you flush the system? You're not supposed to flush these trannys because it usually kills them... or so I've heard... I'm not sure what it breaks though.


Also :welcome: to the forums! :wave:

Thanks Krashed! Nope, didn't flush the tranny.

This problem just started suddenly yesterday, it was driving like a dream before this. As a matter of fact, it caused me to blow through a red light because I was too busy looking at my tach and trying to figure out what the hell happened to notice that the light had turned yellow. Too late to stop before I blew off the red light, LOL.

Oops.

How did you test the solenoids? They tend to stick before they fail so if you checked the coil for continuity that isn't sufficient. I recommend replacing them as they are only about $50 for both. (I've seen them for less on the web).

Flushing isn't recommended 1) most flushes backflow which can loosen sediments and cause problems. There is a system that flushes in the same direction of flow as normal. That one should be OK but you would have to be sure. 2) it can blow the filter out on early trans.

There is a small bracket to hold the filter that wasn't on earlier trans. Your's is in the range they added it. Do you have it?

We put voltage to it and checked for continuity. I guess my question is, could the bench test be irrelevant, in other words...could it bench test fine and still be sticking when under pressure? Could that give us a no shift/no codes scenario?

We are definitely going to change the solenoids, hopeful it helps. Just scratching my head as to why no codes were thrown.

No, mine doesnt have the bracket.

We put voltage to it and checked for continuity. I guess my question is, could the bench test be irrelevant, in other words...could it bench test fine and still be sticking when under pressure? Could that give us a no shift/no codes scenario?



No, mine doesnt have the bracket.


That's what I said. The coil test is irrelevant. The coil can test fine even if the body falls off!

If they stick they may not give a code. Eventually they will but I don't think you want to put it together and wait for that to happen.LOL

I changed the solenoids, checked the wires, and made sure the PCM was sending the ground, but mine still wouldn't shift. I wound up replacing the transmission, but the reason it wouldn't shift was due to a broken 2-3 accumulator spring and both valve bodies needing new gaskets.

That's what I said. The coil test is irrelevant. The coil can test fine even if the body falls off!

If they stick they may not give a code. Eventually they will but I don't think you want to put it together and wait for that to happen.LOLThanks for the clarification. I thought that was what you were saying, but wasn't sure. And no...I don't want to wait until this is worse, LOL.

This is definitely what we are going to do to start, hoping like hell this fixes the problem. I am really not wanting to have to replace the tranny, LOL.

This is a long shot but I will post it anyway.My tps (throttle position sensor) went
bad on my N* and one of the simptoms was it wouldnt shift into overdrive ever.
With alot of sliping, anyway most trans use a cable from the throttle body to trans.
Not the N* they use a reference signal from the tps.I replaced tps never had the problem again. No codes were ever given by the ecm before and after.

This is a long shot but I will post it anyway.My tps (throttle position sensor) went
bad on my N* and one of the simptoms was it wouldnt shift into overdrive ever.
With alot of sliping, anyway most trans use a cable from the throttle body to trans.
Not the N* they use a reference signal from the tps.I replaced tps never had the problem again. No codes were ever given by the ecm before and after.
You are not the first person who mentioned this, it will be the next thing we look into. Thanks for mentioning it!

I changed the solenoids, checked the wires, and made sure the PCM was sending the ground, but mine still wouldn't shift. I wound up replacing the transmission, but the reason it wouldn't shift was due to a broken 2-3 accumulator spring and both valve bodies needing new gaskets.
Thanks, I'll have to look into that, can this be checked without removing the tranny?

It might be a good idea to get the gaskets. They should be reuseable but they can be fragile. If a small piece comes off it could cause strange problems. Most metro areas have trans supply shops, DACCO, RPM, I'm sure there are more. That might be a better place to get parts.

I don't have the manual here so someone else may chime in on the accumalator.

The only way to check the 2-3 accmulator is to drop the tranny. It is located in the second valve body, which is in the side case of the tranny. Mine was constantly in second gear though, no first, third, or 4th. I would change the solenoids first, and then make sure the PCM is sending the ground to the solenoids. My tranny took a beating from the previous owner before the 2-3 spring broke, so I wouldn't be worried about it.

Hi all, I just wanted to update...changed the solenoids and it WORKED!!!!
Like a dream. Zero shifting problems now.:thumbsup:

I wanted to let anyone who is in this situation know that in our case, by all appearances, everything looked perfect when taking it all apart. Every little part looked good. So, even though you may be out 50-75 bucks, it can be worth it to start there. (the kit was around $67 at our dealership, would have saved a few bucks if we would have waited a few days and bought it elsewhere but we wanted to get this going)

Let me know if any of you have any questions, maybe I can be of help to someone else in the future.

Thanks again for all of the helpful responses.

And Thank You for letting us know!:highfive: