Sonko2010

Hi everyone,

New to the group and I just inherited a 2004 TT Quatro, 6 speed manual. It arrived to CA this week from the East Coast. I am curious what your thoughts are on using the 91 octane gas here in CA given the gas cap recommends much higher. Are there any legitimate boost additives?....I am reading many are snake oil and a waste of money. Or is it OK to just go with the 91 octane? With 50K on and lots of life left in her, I would like to take car of her. My Dad would have wanted that.

Thanks for the advice and help.

Chris

randomid123

What is the highest octane rating gas you can get there in California? I would recommend using the best you can get.
I can get 93 Octane here in Missouri.

Vegas-roadster

91 is the best you can get almost everywhere in the far west, not just CA. I've been using it in all my TTs and other high compression cars since 2001 with no issues. The engine computers adjust for octane variations. Do not waste your time with additives.

Sonko2010

Thanks for the replies. I spoke with a local Audi dealer yesrterday who said fill it up with 91 Octane (the highest we can get in CA) and let the computer do the rest. No additives needed. -Chris

lyleswk

You can even put 87 octane in if you want. There will be a slight decrease in power and mileage, but you likely won't be able to perceive it in normal driving. The ECU will adjust the timing as necessary. The reason it is "recommended" is the hp / torque rating was based on the higher octane. All manufacturers do it.

Vegas-roadster

The salesman who sold me my wife's CPO MB E350 said he never uses premium in his MB for that same reason. I always use 91 anyhow. At 10K miles a year, about 25 mpg, and 40 cents per gallon extra over 87 octane, if you can't afford the extra $160 a year you probably should not be driving a TT or E350.

P.S. Just noticed I recently went over 1000 posts! Congratulations to me!

randomid123

I agree with second part, about the cost of the gas, and not driving a TT if you do not want to spend the extra money.

I do NOT agree with the salesman's view point. He is probably driving a new car every year, and turning the "old" back to the dealership. Short term probably OK to use 87 octane, but not long term.

Mister Bally

All I can say about those who say "You shouldn't drive an Audi if you can't buy premium fuel etc," is: Don't tell me how to spend my money.....

Two kids in college does not help. I spend enough in parts & service for my vehicles. I'll use regular and let the Bosch knock sensors and timing thingies do their work.

Yes, I ran Sinclair Premium (only 91 octane available) when I made my Bonneville run as shown in my avatar as well as in one of my photo albums.

lyleswk

The only thing I am particular about is the brand of gas which are very different. Based on my research, I use Chevron or Shell if I have a choice.

All I can say about the long term usage of low octane is I have had 8 cars that all "recommended" high octane. I still have 6 of them:

2013 S5: 51K - Owned since 2014.
2004 BMW 325Ci: 85K - Owned since 2013.
2003 Audi TT 225 hp: 110K - Owned since 2015.
2003 A4 1.8t: 125K - Owned since 2011.
1999 Mercedes ML 320 - Owned since 2000.
1984 Nissan 300ZX Turbo - Owned since 1984.

Bally, I feel your maintaining a fleet. I have 3 boys and am buying parts and getting my hands dirty all the time...

uberwgn

Chris, the gas cap recommendations are for 91 octane by USA standards. Is it different for a 2004MY car?










Our cars all show 91 octane or better. Printed Owner's Manuals show the same.