What type of gas do you use?

[NCC1701]

My experience in purchases of all kinds is that I almost always regret my purchase when I have decided based on saving a buck. Premium is recommended. The difference in price ($2 a tank) is insignificant to me when spread out over the 2 weeks the tank lasts in day-to-day driving.

[gniwok]

I will definitely use the recommended premium at least until the warranty runs out! That way I don't take any chances if there's a problem

~Jas...

[Celt88]

Shell or Sunaco. 93 octane.

[CruzinSusan]

>>the type of gas that has a specific gravity of 0.71, and therefore a weight of about 5.92 pounds per gallon, and releases approximately 19,000 BTU of energy per pound of fuel burned....

jetfuel<<

Jet, I sure wish you'd pay more attention to the details.

Chevron Premium.

[headless]

I have experimented over the 5 years I have had my smart roadster and now I only use Shell Optimax 98, which is Super Unleaded here in Britain, it gives the best mileage and more bangs for your bucks, try to not swap between different grades of fuel too often as the ECU does'nt like it, if you do change grades, take the battery off for 15 mins and the car learns the new fuel faster.
Ellis

[smart fortimo]

Originally Posted by headless

...the car learns...
Ellis

Ellis, I think the car reacts. No?

[eqwalker]

I have always stayed with 91 octane.

[fortow]

Originally Posted by smart fortimo

Ellis, I think the car reacts. No?

Yes - it doesn't "learn"

You're right, the car's computer only reacts to input from the knock sensor which will only detect detonation. If you use fuel with a low octane rating then the engine may detonate and that will ultimately result in the computer retarding ignition timing to help protect the engine.
If no knock is detected then it makes no difference what grade of fuel is being used - the "ECU" will not know what the grade is.
Disconnecting the battery isn't going to help anything - except that it will erase any impending codes and the computer will have to go through the normal drive cycles to reinstate it to the "ready" mode. You may also have to reset the radio as well.

[NeWave]

I use Premium it's only $2 more. Not a big deal.... Shell or Mobil 93.

[mrc59]

What is the diff between 93 octane and 88 octane?

At $0.25, it's $2.

Buy the high octane so you don't FU the engine or your mileage.