Most of the 91 volvo's airbags were not standard. However you can take it to any volvo dealership and have them add if you do not already have them.
pull out ashtray and lighter- realys are behind ashtray
low washer fluid
http://www.brickboard.com/FAQ/700-900/ElectricalCircuitsRelays.htm#RelayLocations
What_could_be_causing_your_2000_ford_windstar_battery_to_not_hold_a_charge
Where is the cooling fan relay for acura legend srs found
Check the headlamp relay in the fuse box under the hood. Hopefully its as simple as just replacing that relay.
As in SRS airbag? I'm going to say with reasonable certainty no as my 91 had no airbag.
The recommended fuel for all Volvo 70 series is premium, 91 RON or better.
Dose a 91 honda civic have a gas light
Behind the Lighter socket is a white box ,w/6 plugs on it, that is a fuel relay switch...replace it
Try looking in the mirror? ha! good one!