wwt

Without meaning to offend anyone here who might be affiliated with that company -- is Sunoco generally recognized as being acceptable grade gasoline for a 2.7T? Around here (Boston) their premium is consistently ~5-10 cents cheaper than other major brands, which has always made me suspicious. I'm now trying to be extra careful with gas, since my almost new 2001 (2500 miles) seems to be suffering from the fuel sender problem, which I thought AoA blamed (partly) on "certain fuel additives" or something to that effect. Thoughts?

hwj

Several S4 drivers swear by Sunoco 94.

pablo1

Sunoco premium (as opposed to Ultra with 94 octane) or any other major brand premium should be fine for your 2.7T as long as its octane is at least 91 and your engine is not chipped. You could probably get away with using less octane since the knock sensors would intervene but your engine would not be able to produce max. power. I mention major brand since having the right detergents to keep your injectors clean is paramount. Chipped engines usually require higher octane. In some cases of chipped engines, knock sensors have not been able to control all detonation so higher octane is a good idea.

milmo

It doesn't matter. Buy the least expensive 92 Octane you can find.

If you're chipped, it's essential you get premium.

Wade(4.2-2.4)+T

Yep. I've been using ARCO for years. No fuel-related problems.

DebauchedSloth

I've been pretty religious about using Sunoco 94, and have noticed:

(a) Mobil 93 is good for about 1 MPG better gas mileage.

(b) *Any* 93 Octane runs much more smoothly.

I am not chipped, that's over ~16000 miles, and, yes, no more Sunoco 94.

Greg

DLow

The extra point of Octane was helping a problem I was having where the engine was retarding the timing under heavy acceleration. (Chipped). Now that the weather is cooler (the problem was in what little heat we had in Boston this summer), I can probably go back to Mobil...but no issues with 6000 miles under Sunoco 94...

Kenny

I have used both premium sunoco and sunoco ultra 94 in the past... My BMW started making pinging and knocking noises, and it was using Sunoco, that my fuel gauge on the Audi started to act erratic... After switching over to Mobil, Amoco or Exxon premium (recommended by my mechanic), I have no longer experienced this on my BMW, and the fuel gauge on the Audi Now out of some miracle works fine after several tanks... I hear certain gas stations cheat, and dont really offer what they advertise.. My mechanic says many gas stations offer 93 premium, but in reality mix the gas with lower quality 89 octane, thus the cheaper prices in 93 premium gases at different gas stations. I have no proof of this, but it ceratinly justifies the different prices in premium 93 octane gasoline at different stations..

RomanQ7-2007

The only real difference in fuel is the additive. Most fuel comes from the same fuel refinery, so the additives may be different even in each state. I remember several years ago, most fuel tested across the country never met its "octane" rating. I would suggest changing fuel brands each time you fill your tank, until you find the right match. I have had very good luck with SUNOCO fuel.