I have a problem I am hoping fellow 'bricksters can shed light on. When the weather is really cold (-20C), if I start the car, drive at highway speeds for 7-15 minutes, and then return to city speeds, the car will stall as soon as the revs get below 750rpm. At this point, the engine appears to be fully warmed (the temperature guage is in the middle). The car will restart, and will stay running, so long as I keep the revs above 750rpm. At city speeds, there is no problem, and if I can keep the car running long enough at city speeds after the highway jaunt, the problem goes away.

The car is an 1982, automatic with b23f engine (fuel injected). During the last cold snap I had the car checked by a mechanic (not a volvo specialist) and they could not recreate the problem to diagnose it. They suggested adjusting the round "thing" underneath the fuel injection rail(?), which I think is the idle adjustment knob, but this doesn't seem to have helped.

After reading this board and Chilton's, my only guess is something to do with the cold start injector, but I have no confidence in that conclusion.

Any thoughts would be appreciated.