85 308 QV throttle hesitation when warm

I have spent the last week reading all the related posts on the issue I am having. This includes Carl Rose's among several others. Yes, I have used the search feature before posting. lol

The car starts on the first attempt when cold or hot and idles at 950-1000. It runs fine when first driving off with great acceleration. When the car gets warm after approx. 15 minutes, the acceleration is poor starting around 2500 rpms. The car seems bogged down and has very low power. When parked, the car easily revs up to the yellow/red line. I always had vehicles which ran better when hot or at temperature.

I have reviewed the Ignition and injection section in the Mondial Workshop manual, the Service Bulletins and the Gasoline Fuel-Injection System K-Jetronic book.

I performed a fuel system pressure check with the following results:
Cold 2.0 bar (29 psi)
Warm 3.0 bar (43.5 psi)
System 4.0 bar (58 psi)
Pressure after 10 and 20 minutes 2.2 bar (33 psi)

Pressures per Service bulletin with my WUR (0 438 140 132)
Cold 2.0 - 2.5 bar
Warm 3.3 - 3.7 bar
System 4.7 - 5.4 bar
Pressure after 10 and 20 minutes 2.7

Question, what is the cause of the poor acceleration and apparent related low fuel pressures?

The threads I have read mention the WUR as a possible culprit. What else may be causing the issue?

Any help and suggestions would be much appreciated.

Thanks,
Bill