if you read the manual i believe it says... 90 is sufficient...though it might say 91 i only use premium b/c u can tell the difference there's a lot of engine ping with the lesser gas
The owners manual states to use 91 octane or higher. I would reccomend 93 octane, especially in summer months. The only way I would run a lower grade is if you had extensive knowledge about altering your spark timing tables safely.
Looking for a Used Grand Prix in your area?
CarGurus has 2,919 nationwide Grand Prix listings starting at $1,995.
Search Pontiac Grand Prix Questions
Pontiac Grand Prix Experts
Related Models For Sale
Used Cars For Sale