Volvo: auto trans overdrive, gas milage, volvo 240dl

Question
i have 1983 volvo 240dl 4cly auto the overdrive quit. i used to be able to hit dashboard and it would shift. i suspect relay but i cant find it. i found several relays behind consol but none changed problem. fuse is good. gas milage is suffering bad. any sugestions

Answer
i'm not sure where the relay is on an 83, but you could unplug relays while seeing which things suddenly don't work, such as a/c , power locks, o/drive, those are the relays in front of the shifter, the o/d relay has grey, green and white wires on later 80's models anyway