Adjust ignition timing. check knock sensor.
You need 91 Octane, which you can use 93 octane and 89 octane mix. which is Premium and Mid grade fuel.
Try 92 Octane.
Meaning 95 octane? Yes, no problem.
Try the higher octane gas you can find.
87 octane regular unleaded.
What could be the problem when a 2002 Volvo won't stay stared
I had to do this on my 96 850, and no, I did not have to have it running, just on accessories on ignition.
For a 1995 Volvo 850 wagon, it is recommended to use unleaded gasoline with an octane rating of 87 or higher. While the vehicle can run on regular unleaded, using premium fuel (91 octane or higher) may provide slight performance benefits. Always check the owner's manual for specific fuel recommendations and requirements.
Despite that Volvo is a Swedish company the founders didn't name the car Viking or Nordic or anything like that. They decided on the Latin word volvere, meaning to roll.
One of your running lights is burned out...
The engine is running C O C K
The engine is not running!