Important tidbits to include:

fuel injection? Carbs?


A quick guess is that you're using a fuel injected car and the ignition
points on the distributor are shot. Cranking the gas pedal will cause the
injectors to fire independently of the distributor mounted points.

Unless you know of a place that works on old volvos, if you take it
to a shop find a shop that works on old VWs (air cooled). They also
used the d-jet fuel injection so will know more than most places.
chris