The cold running problem could be due to valve deposits initially soaking up the extra (cold temp) fuel and starving the cylinders until the deposits get saturated. The cure (?) is to mix a good quality Fuel Systen cleaner like Chevron Techron with the gas. It may take more than one treatment.

As to whether the pumps should run with key ON? I say for your 87, No. But I'll bet you get a lot of yesses too. I think it is true for later cars like my '93 940, but I have never seen the so-called "2-second prime" defined in any Bosch or Volvo documentation. I know that it does happen on '80s cars, but I think it's a fluke.
--
Bruce Young,
'93 940-NA (current)
'80 GLE V8 (Now gone)
'83 Turbo 245
'73 142 (98K)
'71 144 (track modified--and still here)
New 144 from '67 to '78
Used '62 122 from '63 to '67