Gasoline in Audi A6
 

I have a question. This may sound stupid but, I was wondering about the type of gas I use in my A6. The manual and gas cover say to use premium octane 91. I usually use 91 but sometimes use the cheaper one which is 87 octane. I wanted to know if this does any damage to my engine or is it safe to use 87. And wuld this change my MPG in anyway. Also what are some of your averages in terms of MPG. I have the 98 Audi A6 non-quattro version..

THANKS

RE: Gasoline in Audi A6
 

hey there, i have the exact same question, on my 96 the fuel cap says use highest octane, everytime i pull up to a fuel garage they wana put in unleaded??? i just usually alternate between lead and unleaded ,if its a good high performance fuel i put in leaded, if its a dodgy fuel station i put in unleaded...,ive discovered the car pulls beta that way..

RE: Gasoline in Audi A6
 

You can use either actually. The 91-93 is a higher octane obviously and will run the car at ahigher degree of preformace, however the car will also run on 87 octane if you choose. I believe the manual actually has that written in it towards the back under the specifications section. It would be near the area that talks about the kind of oil to use which by the way is SAE 5W-20. Here is the exact wording on the fuel:

Fuel Requirement 87 octane unleaded regular gasoline;
91 octane unleaded premium for best
performance

You can also run 100 octane fuel in the car if you get the tuner chip with the 100 octane program. I havent run that high of octane fuel yet since I have a few other things to do to the car but its certainly on my todo list :)

RE: Gasoline in Audi A6
 

http://en.wikipedia.org/wiki/Octane_rating

RE: Gasoline in Audi A6
 

OH NO the octane discussion again!

OK -- Octane is a measure of the fuel’s ability to resist pre-ignition AKA detonation. Higher compression ratios, advanced timing, and heavy loads (racing) require higher octane. Under normal driving Audis work fine with 87. If you chip the car, you probably want 91 but many Audi’s have knock sensors that let the ECU know that pre-ignition is occurring and it adjusts the timing accordingly.

100 octane does not increase performance over 87 unless you do something else – timing, compression ratio, etc..
I travel 100 miles a day for work so I buy 87 for my cars. Just can’t justify the added cost of premium fuel with its additional 10 to 15 – sometimes 30 - cents a gallon cost.

RE: Gasoline in Audi A6
 

Thanks for the link , that was a great read.....

RE: Gasoline in Audi A6
 

That link will answer your questions better then what anyone can explain to you.

RE: Gasoline in Audi A6
 

Abbot, I still miss your signature on the S-line...thing. If possible, put it back...it used to make my day, everytime I saw it ;)

RE: Gasoline in Audi A6
 

I was actually wondering this also...

My dad who is a car enthusiast told me to put in the 93, so thats what i did today. Its the first time I put gas in my 4.2. Was expensive though, after reading this I may just put the 91 in next time. doubt I will put in 87 though

RE: Gasoline in Audi A6
 

i put in the 93,anything other than that will mess ur audi up,at least that what i was told by the audi dealer