What does this sound like to you?

[99V8SHO]

I only really notice this happening when the tranny is warm. I will accelerate at moderate pace in first, it will shift to second before 3500, then I will try to hold second gear out to at least 4K so I can hear the secondaries open (gawd I love that sound). Sometimes the tranny will granny-shift into 3rd, even at 1/2 throttle in second. So I floor it to make it downshift, and all it does is do a third gear pull, instead of downshifting to second. I would be flooring it right around 35-40 which is plenty low enough to go down into second. From a stop after this happens, I floor it in first and eats up the revs in first like normal, then it shifts into second, like normal, then at aroud 5K RPMs in second, the revs will drop for about a half second down to about 4500 then start climbing again. I know this happens in most gen3s in 3rd gear, I have seen a few dyno runs of gen3s and it happens to everyone. But it happened in second. That has never happened before.
Other times it feels like the tq convertor doesn't know what it is doing. With climate control off, (again when tranny is warm) going highway speeds, I nudge the throttle to pass someone, and the convertor unlocks for a split second then locks itself back up immeditately.
The tranny was rebuild about 1.5K ago or so. AFAIK the shop warranties its work for 12K or 12 months, whichever comes first, so if the tranny fails again, no big deal. But it is really annoying. I search for power at low speeds and I don't get it like I am used to.
Since it only happens after warm-up I tend to believe that the fluid is overheating or something. Luckily my spring break is coming up next week so I can take it back to the shop and have them look at it then have the shift kit and tranny cooler installed that have been sitting in my backseat forever. Maybe that is all it needs.
Any ideas? Sound familiar?

 

[SHO#7]

Here are my thoughts on this. First, I would have my codes read. You never know what is in the system, even with the SES lamp off.

Second, the TC unlocking when you accelerate on the highway " to me " is normal. The car can accelerate easier with the TC unlocked. And it locking right back up once you are at a steady constant throttle sounds normal to me too.

However the not kicking down issue sounds like a possible TPS sensor out of range. And if the TPS does not tell the transmission that you are accelerating enough to call for a down-shift. It will not DS. And that would also make sense with you feeling the " difference " with your lock up when calling for throttle on the highway.

What I would do is have my car put on a scanner with an option for data display, ( not just a code reader ) and look at the TPS. It will change from C/T ( closed ) P/T ( part open ) to WOT ( wide open ) depending on where you have the accelerator. Also... And I am not 100% on this part, but at WOT it should read approx 4.5 volts.

In either case, good luck.

 

[SHOZ123]

You might want to test the resistance of the TCC solenoid. This was failing on my car and would cause the TCC to disengage easily at highway speeds and not re-engage after the car was warm and had been driven for a 1/2 hour or so.