95 Lesabre won't shift

[BillD]

My 95 Lesabre is starting to act up since it's getting cooler out. First noticed it last winter. Starting out on a cool morning, it will shift thru 1st and 2nd fine, but I just get "neutral" when it comes time to shift into "Drive". No go! What's weird is if I stop, put it in Reverse and brake torque it a bit, it will then shift normally in "D". The only time it does this is when it's cold outside. The car ran flawlessly ALL summer. Any ideas??
Thanx!

[maxwedge]

Usually this is an internAL, SEAL PROBLEM, A FULL SCAN CAN LOOK AT SOLENOID FUNCTIONS TO SEE IF IS ELECTRICAL.

[BillD]

Thanx Max, Yeah, I was sorta thinking seal as it must be shrinking with the cold. But was not sure if any solenoids could be reacting to the cold as well. Sorta hoping it is as they're easier to change as opposed to the seal(rebuild). I guess I'll have to get a dealer to do a scan as this car is a tweener OBD1.5 which is a major PITA when trying to diagnose anything!

[Blue Bowtie]

Verify the proper fluid level, connection at the front electrical connector, position of the neutral switch (TRS), connection and condition of the vacuum modulator, and condition of the filter and pickup tube.

There is a slim chance that the problem is in the accumulators (accessible via a pan drop) or the oil tubes from them.

A scan, a line pressure test in every range, and better diagnosis of the solenoids (actual measurement of the resistance instead of just plugging a scanner into the ALDL) might help narrow down the possibilities.

Does the symptom change once the transmission is warmed to operating temperature? Is the condition different if you manually shift through the ranges? Are there any unusual noises when the trans goes to "nowhere?" If you briefly test drive with the vacuum modulator vacuum line disconnected and plugged are the symptoms different?