Does it matter what kind of gas I use in my 05 Audi A4 1.8T?

vw/audi call for 91 octane in the 1.8t.

don't use anything below that.

Sense I can remember the Audi/Volkswagen 1.8 Turbo engine has always required 91 octane (premium). On almost all turbocharged and high compression engines, 91 octane will be required. However manufactures program the cars ECU to run on lower octane gas as well, because they know that once in a while some one will accidentally put lower grade fuel in their vehicle. But for optimal engine performance and life stick with 91 octane, your Audi will thank you for it.

right it is the take care of octane ratings (only placed) because you've a intense performance engine , your minimum octane score must be 89 (this is going to inform you on the in the gasoline lid)... in case you employ an octane it is lower than the minimum, you could wade through engine harm and knocking (knocking isn't a reliable sound to take heed to)... actually, once you employ a low octane gasoline on an engine that calls for a intense octane gasoline, your engine will be placed right into a community of inefficient combustion- subsequently ensuing in decreased potential and decreased gasoline economic equipment... to interrupt it down more desirable (if conceivable)...the octane score of gas tells you the way a lot the gasoline may be compressed before it spontaneously ignites. at the same time as gasoline ignites by using compression really than using spark from the spark plug, it motives knocking in the engine. Knocking can harm an engine, so this is not some thing you opt to have taking place. also, utilizing higher octane gasoline in a vehicle that calls for a decrease octane gasoline gained't advance gasoline performance or potential because the engine isn't able to this compression ratio

Use only premium fuel. Turbocharged engines are very susceptible to pre-ignition, which is caused by low octane (uncontrolled burning of the fuel). Due to the nature of turbocharging, pre-ignition can be detrimental - you can melt pistons!

Just don't do it. You're gonna save a few pennies a gallon and risk your engine? Also, Audi may deny a warranty claim if you don't use the correct fuel. Follow your owner's manual!!

Greg

If your running a turbo under the hood and you drive with alot of short starts and stops, you're gonna wanna run higher octane regularly. If your doing alot of long drives with it, you can get away with a lower grade fuel but after every 4-6 months i'd run a couple of tanks of premium and use water removal and power booster additives. This will help keep your injectors clean. Don't forget the regularly scheduled maintainance.

You have 9.5/1 compression ratio on turbo A4 it was designed to run on 91 octane fuel..You will feel no significant difference if you use premium grade fuel.Mick UK own and work on Audi.

The only gasses that go in your car technically are atmospheric gasses: Rougly 80% Nitrogen, 20% Oxygen and a dash of Argon. If you want better performance, try putting in more atmospheric gasses in your car(via turbocharger).

As for gasoline, no, a higher octane will not make you go faster or get better mileage.

(btw, great car)

if your car was set to run on premium(91) then you will notice a difference with lower grade fuel

premium if you want performance out of your car

always do what the manufacture suggest on the gas door