Date: Mon, 6 Mar 2000 21:01:13 GMT
From: (Goran Larsson)
Subject: Re: New 9-5 SE

In article <>, Winston <> wrote: | It makes sense that you will feel a difference with lower-octane fuels, as | the engine computer will retard boost to prevent knocking. However, as | the engine computer analyzes the fuel-air ratio and many other parameters | thousands of times per second, I don't think you have to worry about your | car not properly noticing or adjusting to this change. Your engine | computer already jumps through hoops to makes sure that your car gets the | proper fuel-air ratio when warming up after a cold start. Surely the | difference between 87 and 92 octane won't throw it. The Trionic system will adapt/train itself to the fuel quality you feed it. It learns how much boost it can use, how it can adjust the ignition, and so on. This adaptation will take a while depending on how you drive, but 300km of varied driving is a goof bet. If you then feed it a lower octane fuel it will try to use too much boost or retard the timing too much resulting in knocks. After a while it will adapt, but if you constantly change fuel quality it will have to adapt all the time. | If you're so inclined, there doesn't seem to be anything wrong with using | regular as opposed to premium fuel when you're doing mostly highway | driving and won't be using full boost at cruising speed anyway, unlike in | city stop-and-go driving. Full boost in city driving? Are you completely mad? -- Göran Larsson hoh AT approve DOT se I was an atheist, http://home DOT swipnet DOT se/hoh/ until I found out I was God.

Return to Main Index

The content on this site may not be republished without permission. Copyright © 1988-2020 - The Saab Network -
For usage guidelines, see the Mission and Purpose Page.
[Contact | Site Map | on Facebook | on Twitter | Shop Amazon via TSN | Site Donations]