I haven't been using 91 octane...

[dbovar1]

could this cause a lose of power on the low end

[yodawill2000]

It will cause the Knock sensor to retard the timing below 3K.Not good for your engine either.

[dbovar1]

thats exactly whats going on...thanks. Filling up with 91 right after work!

[driverdriver]

Not driving with Octane 91 can also screw up your injectors. Its a special pistol design. Perhaps Q45tech can explain?

[Victor]

Why would regular gasoline used in place of the recommended premium screw up injectors, unless it was causing preignition detonation, which would also eventually destroy the tips of the sparkplugs and even pistons if bad enough.

[Infinitiguy19]

This is a topic of great debate but regular or even mid grade gas is not as "clean" refined as premium gas. But I wonder why in Nissan's its OK to use regular or mid grade I think and in Infiniti you HAVE to use premium.

Point is just use whats recomended, Plus you should be less worried abot putting gas in the car and more about fixing the problems that will soon arise. Hell you will have more problems with using regular (Water) gas that premuim (Supposed real gas).

Unless it was causing preignition detonation, which would also eventually destroy the tips of the sparkplugs and even pistons if bad enough.

Thats exactly what regular does!!!

More info: http://www.nicoclub.com/articles.php?id=416754