Mark,
funny, but I discovered the same on a friends new P160SX a week ago!
It was set at Uacclr1 at 0.200 volt, we increased it to 0.275 and it would start fine. After a few flights we put it down again to 0.225V, works perfect.
Maybe connecting a 1.5V battery to the pump for 30 minutes (pumping fuel!) would help...
Uacclr1 can be reached in different ways, but "Limits" together with "+" is one of them