[ccervenka]

Maybe our ECUs need an electric blanket per this thread: 2001 slow to shift (or not shift) when cold

In all seriousness, maybe consider taking a hair dryer to the ECU the next cold day and seeing if the shifting is similar to when it warms ups normally. BTW, what do you consider as 'cold'? Here in WI anything below 0F is 'pretty cold'.

 

[ccervenka]

After first start of the day (Cold):
1. Park - Reverse sometimes clunks sometimes normal
2. Reverse - 1st has a slight almost unoticable delay and you can tell that the tranny is binding up as if 1st Gear cluth engaged before Reverse disengaged
3. 1-2 shifts are always NORMAL - Smooth
4. 2-3 shifts are always Hard - Van lurches forward then sudden deceleration as if it engaged 3rd before disengaging 2nd. Duration of this bindup is split second...as in it doesnt manifest any body motion or nose dive. More like .2 seconds where you feel it as two thumps

+1 thanks for the details! ....I've got the exact shift conditions you've described on 1-4.

Here's another thought: You've replaced the A/B solenoid, but have you adjusted it? It appears that small pressure adjustments are suggested (1/8 to 1/4 turn at a time). Maybe this is worth a shot? If it doesn't work, you can always go back to the original setting (use white paint to mark where you started).

Here's some thought-sharing from our friends at Sonnax:

Honda/Acura 4-speed (3-shaft) and 5-speed transmissions often exhibit soft shifts and/or low line pressure rise. These concerns can be caused by incorrect or soft factory calibration of the clutch pressure control solenoids (CPCS), and further aggravated if there is line pressure leakage within the transmission. The PCM controls shift feel and overlap through CPCS A and B in conjuction with shift control solenoid C. Adjusting CPCS A and B can result in firmer shifts and increased line rise. Sonnax has developed pentagonal-shaped solenoid adjustment tool 88950-T to fit the recesses of solenoid adjuster screws.
•Allows proper adjustment of solenoid block
•Transmission removal not necessary

Here's the link to the part description
....and to the instructions

 

[ccervenka]

Sorry to tack more on, but here are important points from Sonnax's instructions that may help us identify and cure shift symptoms:

Adjusting Solenoid Block
1. Place pentagon-shaped tip of solenoid adjustment tool into adjuster screw recess of clutch pressure control solenoid “A” or “B.”
2. Turn adjuster screw 1⁄8 to 1⁄4 turn clockwise to increase pressure for solenoid "A", and counterclockwise to increase pressure for solenoid "B".
CAUTION: Exceeding 1/4 turn can result in a downshift clunk. Adjusting ratios will not compensate for severe unit wear or a defective solenoid.

Adjusting solenoid ratio “A” will affect:
• Reverse servo control and Reverse engagement
• 1st clutch Forward engagement
• 3rd clutch feed and 2-3 upshift
• TCC lockup RPM slip rate in 3rd only

Adjusting solenoid ratio “B” will affect:
• 2nd clutch and 1-2 upshift
• 4th clutch and 3-4 upshift
• TCC slip rate in 4th