Stella

Using 89 instead of 91 gas. Will it hurt my engine? Thanks!

Sharm

might be a false economy, because you'll lose a bit of performance and fuel economy which will cut in to your savings.

But the car should cope with it just fine.

oatzel

if you're not chipped you should be fine. as Sharm said, the computer should knock timing back

Stella

How strange, i'm getting BETTER economy with the superior vs premium gas. ???

paul_858

knock sensor voltage, it will start correcting and reduce timing. This doesn't mean you should run 89. However the car should compensate to some degree for lower octane. Should you run 89? No, never. Could you? probably. Is there added risk? of course.

mitchelm

I have the AMS, and from my experience with lower octane gas, you are pretty much fine unless you floor it in 4th or 5th gear. Thats the only time i've felt it cut back on the timing. Other than that, I have been fine.

paul_858

that doesn't retard timing.

Sharm

Hmm - odd, don't know why that would be. The car will take it, but it's not the best thing for it.

jim'02a4

why don't you just use 91? Say for example there is a 10 cent per gallon difference, and you use 30 gallons a week ( thats a lot of driving) you are saving what,,, $3.00? It comes to $156, per year. Is this savings worth it?

palewhitemale

of power too. I'm amazed at the difference in feel between 93 and 91, I wouldn't ever put 89 in the car.

I'm glad there's a 76 with 100 at the pump near me.

bill