Wondering what the REAL difference is...
Thread Starter
New Member
Joined: Sep 2000
Posts: 42
Likes: 0
Wondering what the REAL difference is...
I was down in South Texas over the Holidays, and my wife and I even ventured into Mexico for a few days. Upon our return stateside, I noticed that my tank (95 90 Sport) was too low to make it back to the next major metro, so I acquiescently pulled into the nearest gas station and used the gas that was available (i.e., 87 octane.) Once back on the road, I expected at the least some minor objection from the engine, but to my surprise the engine performed flawlessly (in fact--though probably my imagination--the engine actually seemed to perform a little more smoothly than it had previously). In retrospect, I have always been very nervous about using anything but super unleaded (91 octane), but today I find myself a true doubting Thomas. Have I been overly cautious, naïve in thinking that 87 would irrevocably ruin the car's performance and longevity? I ask this because I can't escape the sinking feeling that it really just does not make that big of a difference. Anyone else feel this way? I am sure that I speaking out of total ignorance, so if some of you mechanical gurus would like to explain to us plebeians WHY we must run higher octane rather than normal cheap stuff, we can forever feel better about spending 20 - 30% more at the pumps than Joe Q. Driver. (Please remember, laymen speak in laymen's terms)
AudiWorld Super User
Joined: Mar 2000
Posts: 9,281
Likes: 1
That "must" have been in your head.....
...if I even put 89 octane in my '95 it feels like I'm driving a 4-cyl. If I drop 87 octane in my '90 or '91 I also feel a huge difference.
Did you "get on" the gas yet?? That's when you'll notice the difference. When you get on the gas with lower octane the knock sensors will retard the timing. This will only occur WHEN you get on the gas. During normal cruising you shouldn't notice any difference!!!
That had to be your imagination!! Or your car isn't running up to snuff to begin with???
---
Andrew
90 80q
91 90
95 90q
Did you "get on" the gas yet?? That's when you'll notice the difference. When you get on the gas with lower octane the knock sensors will retard the timing. This will only occur WHEN you get on the gas. During normal cruising you shouldn't notice any difference!!!
That had to be your imagination!! Or your car isn't running up to snuff to begin with???
---
Andrew
90 80q
91 90
95 90q
AudiWorld Super User
Joined: Mar 2000
Posts: 9,281
Likes: 1
Maybe this will help!!
<A href="http://www.ftc.gov/bcp/conline/pubs/autos/octane.htm"><B>Octane Info</B></A>
and here's another..
<A href="http://www.zhome.com/ZCMnL/PICS/detonation/detonation.html"><B>Knock Info</B></A>
and one more for good measure..
<A href="http://www.njautocare.com/garage/repairqa/ques071.html"><B>Octane and Knock Info</B></A>
HTH!!
---
Andrew
90 80q
91 90
95 90q
and here's another..
<A href="http://www.zhome.com/ZCMnL/PICS/detonation/detonation.html"><B>Knock Info</B></A>
and one more for good measure..
<A href="http://www.njautocare.com/garage/repairqa/ques071.html"><B>Octane and Knock Info</B></A>
HTH!!
---
Andrew
90 80q
91 90
95 90q
Thread
Thread Starter
Forum
Replies
Last Post
visatrade
Audi 90 / 80 / Coupe quattro / Cabriolet
15
Jun 27, 2016 03:48 PM
Milpower
Audi allroad
7
Jul 13, 2004 06:52 AM
