1991 Volvo 780 Repair and Maintenance
A guide to problems, costs, maintenance and repair for your 1991 Volvo 780
Verified by mechanics, reported by drivers like you
1991 Volvo 780 Problems
The fuel pump relay may fail resulting in a "no start" condition, the engine will crank over but will not start and run. Checking for proper fuel pressure would be the first step in diagnosing this concern.
Engine stalling/stumbling problems can be caused by a failing mass airflow sensor.