Dealer filled my new FRS with 87 octane; Should I flash ECU?
 

Hello,

I bought a 2014 Scion FRS a few weeks ago, and about a week ago I found out the dealership filled the initial tank with 87 octane.

Upon contacting the dealer and notifying them that their own car requires premium, they at first tried to deny it; but upon providing clear evidence they admitted that it does indeed require premium and that,

"It will be fine, just start filling up with premium from now"

I am now running on 92 octane (highest I can get in Washington), but I'm wondering if that inital tank of 87 octane might have permanently set my ECU's timing down.

The car does not seem to perform as well as other FRSs out there, anecdotely... It may just be my imagination, but I figured I would check with you guys and see if anybody else has found a confirmed answer to this question.

Should I go back to the dealership and ask them to flash my ECU? Or will the ECU slowly learn back it's timing with 92 octane gas?

Thanks!!

The ECU will slowly learn, and you should be taking it easy on it and varying your RPM during the first couple tanks anyways.

Thanks Tut!

Just a quick aside, I have to admit that I accidentaly (Honest.. Lol) pushed the RPMs to 5,500 once. It only stayed that high for a split second, and I have not pushed it above 4,000 since. Should I be worried? I was mortified when I realized I did it, after reading the warning in the owner's manual.

Thanks again for the advice!

nothing to worry about, the dealer did the same with mine... after i ran that tank empty, i only filled with 93 shell gas and the car runs nicely

Sounds like you need to strongarm the dealership into giving you a brand new FR-S with the right gas.

LOL :lol:

You are fine. Just drive till the gas is gone refill you are ok. If you are worried about the ecu just pull the negative terminal off the battery for a few minutes.

No, you needn't worry. Your wonderful new car is just fine.

While I am "old-school" in my break-in methods, I know of no long-term studies showing it to be any better for durability or longevity or even performance.

I once had an experienced Honda dealer ask me if I had installed a different chip in the Si we were trading in; he thought it performed better than anything he'd driven before. It was stock, just normal tune-up specs done by me.

Who knows whether break-in methods really matter at all.

But, one thing is certain: An occasional excursion to higher rpms during break-in is not going to do any harm, either short- or long-term.

Rest easy, and enjoy that terrific new car! :)

Thanks Porsche! I'm super paranoid by nature so your reassurance makes me feel a whole lot better.

I'm going to allow the ECU to adjust slowly, as it does seem to be getting better everyday I drive it.

Thanks again everyone for your responses!

:respekt:

Not really funny when there are more than few threads where people have asked about demanding a new car because of some minor problem. Mine ran just fine when I put 87 octane (on purpose) in it.

Its funny because of that. I work at a car dealership I see it every week. :mad0259:

Nothing to worry about, they even dyno the car at the factory prior to shipping to confirm that it's running the way it should. Just dont do it anymore lol

Unless you make them, no dealer puts the expensive stuff in, why would they? Maybe expensive cars but even then I doubt it. Who's going to pay someone to test their fuel on the first tank to find out?

They knew what it takes, it says so right there when they open the fuel door, and for that exact reason. How could anyone work at selling cars and not notice ever in their lifetime that the fuel door tells you what to put in it? Of course they knew.

The manual also says emergency runs over 4k are OK.

UPDATE:

After another tank of 92 through the engine and not a lot of performance increase, as well as a few odd issues that seemed timing-related, I decided to go ahead and reset the ECU. I filled it up with Lucas Oil Octane Booster + a full tank of 92 octane Shell V-Power, then pulled the plug on the battery for a few hours.

Upon reconnecting the battery, I drove it 60 miles in varied environments (on and off the highway), then sit it over night, then drove it another 60 miles the next day. The results have been really good. It seemed to be something of a magic bullet, solving numerous small issues I was having with the car.

Issues include:

-Not rough, but maybe.. Shaky idle? A bit of hunting, and the engine just didn't seem to like idling.

-Throttle Delay. Not to be confused with the throttle dead spot you get after resetting the ECU for the first 100 miles, it just seemed that when shifting into second or sometimes third gear, there would be a slight hesitation in the throttle, like a latency almost. It didn't affect first gear or 4th/5th/6th.

-White Smoke coming out of exhaust at idle. It would happen about 75% of the time, warmed up or not. It only came out at idle, and if I was actually moving at any speed beyond 1mph there would be no visible exhaust smoke of any kind.

-Slight "Rattle" noise coming from the engine compartment. It was clearly audible in second and third gear acceleration, but not in first or 4th/5th/6th gear. It would happen about 75% of the time, about the same rate as the white exhaust smoke at idle. It sounded sorta like there was some change rattling on top of the engine... Very odd sound.

I am happy to report that one ECU reset & 150 miles later, ALL of the above problems have been resolved. There is no more exhaust smoke at idle, once warmed up. The rattle has completely dissipated, and the engine feels solid at idle. It does still hunt occasionally, but way less often, and the engine doesn't feel shaky when it kicks in.

The "Throttle dead spot" was definitely there for the first 90 or so miles, but it went away and the car now accelerates very naturally and the engine sounds super clean on higher revs. When shifting into second and third gear, there is no more "hesitation".

Oh, and on top of all that, my fuel economy increased from 23.5mpg average to 29mpg average! WOW!

Just wanted to share my results with others that may face this issue. If your dealer does fill your first tank up with low-quality/low-octane gas, I HIGHLY recommend the ECU reset after you've run a few high octane tanks through the engine. It has breathed new life into my car's performance.