Engine 93 gas vs 89 gas

my needle jumps around like crazy after about the first 1/4 tank of gas

Man I'm glad its just not me. I'm still wondering why it does that.

It's purely a design flaw in the tank and wherever the sensor is for the tank level. Pretty sure that's normal for any car.

the only time that i actually use 93 or 94 octane gas is when i go thru AirCare in BC where they inspect if ur car's emission is within the standard... test is required every 2 yrs... it is a requirement for renewing insurance... cost $48cdn... last time i tried using 87 octane to go thru AirCare and i barely pass but every time i went b4 i used 92,93 or 94 octane gas and i pass w/ no problems...

The grade of gas will not effect the Corolla eninge. The XRS might require Premuim, but other than that it won't do anything.

I was starting to think its my trd muffler and intake. But i guess not. I've always had around 250 miles per tank. But right now i'm having 210ish. So idk

My 3S-GE requires it.

your wasting your money iff you buy high octane gas. the corolla engine was made for 87 octane. you should only buy higher gas if you are running boost of some kind. higher octane gas burns at a higher degree. it helps to retard the timing so you don't ping or backfire. it won't improve your milage or horsepower if you get the highest octane gas. only thing to watch out for is that some gas at the lowest grade is considered dirty, however, i have read that some high octane gasses are just low octane gasses with boosters in them. i would recommend shell v-power, only because they keep saying it has 5 times the cleaning agents of other gasses. as the the gas i put in my corolla and my tC? i use 87 octane, i'll worry about the tC getting dirty inside in about 7 years, i'll just use seafoam to clean it out then

Boost isn't the only reason -- high compression and/or nitrous like higher octane as well.