l just got a WRX STl and the dealer filled the tank up with regular gas instead of the required premium grade fuel. Is it safe to drive the car till l use it up and get the right gas in it. Got the car from a carfax dealer not subaru.

as long as the engine doesnt start knocking

find the owners manual and see what the manufacturer says in the specs, you`ll probably only expect some pinging and predetonation, but that can screw up a motor big time in the laong haul, if you are really desperate, get some octane enhancer chemicals from your local auto parts store

Subaru engines are well-built enough that 87 octane rating wo not make a difference from 91. At best, you can only hope to extend your engine is life by 1 year out of 15 by using premium, and the horsepower difference will be negligible.

Go to your local napa part,s store or auto zone get you a can of gasoline additive .put it in your gas tank it will jump the gasoline up to mid grade or two can,s will jump it up to high test.

you can use it in a pinch,just dont try and get on it until you use up the tank,as long as you take it easy you wont have any problems,besides,its a new engine so you shouldent be abusing it for the first thousand anyways

First off, the STi requires premium. You're looking at some pretty nasty stuff happening if u run it on regular, such as detonation. Stay out of boost. Keep it below 2800 rpms & baby the hell out of it (light throttle) until u get down to 1/2, then add Premium. After this, u should be okay, as long as u do not go WOT until you've burned through most of this gas & refilled again.

Octane boosters off the shelves at ur local auto parts stores wo not do anything, unless u think taking ur octane rating from 87 to 87.2 is something. If u can find some Torco, add that, but the other stuff is crap.

Absolutely NOT.
You will cause damage to the engine and also will not get the fuel efficiency that the engine is designed for.

Make the dealer drain the tank, thats unexcusable.

But if thats not happening.
Subaru designed safety features into the car for emergencies (ie. u r running out of gas in the middle of nowhere & only 87 is availible). The Sti is ecu will recognise the lower grade fuel & compensate for it. Your car will feel much slower, & even when u refill with with premium fuel it will take time for u car to feel ''safe'' enough to return to its more aggressive engine mapping.
So u can run this fuel in emergencies, & ur car will be ok.

Use a little, top up, use a little more, top up again. l doubt if it was totally empty when he filled it up, so you have a dilute solution, and topping it up every 100 miles will gradually bring it back to what it should be. Just do not floor it or drive over the limit on the highway until the gas is changed.

l agree with Bob.go get some octane booster. If you do not have an auto parts place nearby you can even get it at Walmart.