RPM fluctuation.....

[flippy]

I have OFT tune stage 2 v2.04 it raised the idle from 650-750
the RPMs still drop when braking but it doesnt go as low as 550 anymore
550 rpm is rough and shakes but 650 is okay
and it's never stalled before on idle

[arvidj]

Originally Posted by Koa

Did you get the TSB flash updates ...

The dealer had the car for two days and ensured that the software was the latest and greatest available from Scion.

Originally Posted by Koa

Have you tried tuning? ...

I am not exactly sure why I should invest in after market tuning when I think I have every right to expect Scion to deliver a vehicle that idles correctly in the first place. I gave them 100% of the money they were expecting and they seem to be happy to give me 99.5% of the vehicle I was expecting.

Originally Posted by Koa

Steve hit it on the head.

We agree that Steve did "hit it on the head" in that they don't seem to have it all sorted out yet.

Originally Posted by Koa

... Your 50 years of automotive experience is nullified by the vast changes in car ECU architecture and implementation. Do you realize that it's above and beyond just simple mechanisms and that our idle is controlled by a complex ECU? ...

Really?

And all this time I thought that "fly-by-wire" systems meant that they had decreased the size of the throttle cable.

I also did not know that one of the significant engineering trade-offs required during the advancement of automotive technology was "it has become so complex that the engine will no longer idle smoothly".

I also find it strange that the technological advancements and increase in complexity have not affected all vehicles. There appear to be many available that do not exhibit the idle hunting that the FR-S does. Why is that?

When you are thru insulting my intelligence maybe we can have a meaningful conversation.

[Koa]

Originally Posted by arvidj

I am not exactly sure why I should invest in after market tuning when I think I have every right to expect Scion to deliver a vehicle that idles correctly in the first place. I gave them 100% of the money they were expecting and they seem to be happy to give me 99.5% of the vehicle I was expecting.


When you are thru insulting my intelligence maybe we can have a meaningful conversation.

You're creating a problem in your own head by saying the vehicle does not idle "correctly". What is incorrect about this? Surely with 50 years of automotive experience you can tell us how this is hurting our engines and is not "correct" for the car's stock configuration?

Sorry but as soon as you started throwing around your 50 years of auto experience it opens you up to critique

I will leave with a valuable, relevant piece of perspective that may explain why I feel the need to contest your stance on the ordeal:

"Learning over knowing"

I am anxious to learn how this "idle hunting" behavior is adverse to our engines, trust me I want to know!

[Tcoat]

Originally Posted by arvidj

I am assuming that the thought that I am intelligent enough or over the past 50 years of owning and working on cars have accumulated enough knowledge to know what "an accessory kicking in" might look like is beyond your abilities.

I became familiar with this phenomenon in my first air conditioned car ... a new 1973 Pontiac Grand Prix.



Given that I have owned cars for over 50 years I believe I can answer 'Have you guys driven literally any other car?" in the affirmative. Given that I have never had a car that exhibited this type of idle I find the FR-S behavior strange. Examples of cars that I have recently driven that do not exhibit this behavior includes the new Camry I used while they had the FR-S in for diagnosis, the wife's Yaris, either of my MR-2's, our Toyota truck, the neighbors Toyota truck, the other neighbors Dodge Ram, the son-in-laws Ford truck, ... but that is only in the last 6 month.

...

Where to start?
The first 30 years worth of cars do not mean shit in this case! Mechanical advanced timing and adjusted carburetors did not have the fine responses the electronically controlled engines do (come on you know that).


The 73 Pontiacs were sadly lacking in computer controlled systems of I have been very wrong in how I worked on my cars.


Great, you drove a bunch of cars but I do not see any Subarus on that list. After "50 years" of owning cars I would think you know that different makes can have different traits.


You want something to be wrong sooooo badly that when the dealer and several very knowledgeable people tell you that the situation is normal you throw out your 50 year of expertise as your only answer? That is the kind of shit that makes the older guys look bad on here!
If you are so sure it is wrong take it to another dealership or shop and get a second opinion and then another, and another. If you just keep fishing you find somebody that agrees with you

[Ultramaroon]

Originally Posted by arvidj

And all this time I thought that "fly-by-wire" systems meant that they had decreased the size of the throttle cable.

lol

Originally Posted by arvidj

I also did not know that one of the significant engineering trade-offs required during the advancement of automotive technology was "it has become so complex that the engine will no longer idle smoothly".

I also find it strange that the technological advancements and increase in complexity have not affected all vehicles. There appear to be many available that do not exhibit the idle hunting that the FR-S does. Why is that?

I don't know why they're struggling so much with compensating for the AC compressor but it's a little annoying to me.

I don't care beyond that because it's not damaging the engine at all. Oil pressure is just fine for an excursion to 500 RPM with no significant load.

[BRZnut]

Originally Posted by arvidj

I am assuming that the thought that I am intelligent enough or over the past 50 years of owning and working on cars have accumulated enough knowledge to know what "an accessory kicking in" might look like is beyond your abilities.

If my assumption about your abilities is incorrect then please explain to all of us why this phenomenon only appears if the vehicle is in park or neutral? Is there some special accessory that only kicks in when in park or neutral and when in drive or reverse does not kick in and therefore the idle is rock solid?

Please feel free to elaborate on your description of this special accessory.

Here is a visual aid to assist in you explanation ...

Be sure to explain why the idle will be at 750 RPM, then slowly drop to 500 RPM, then quickly accelerate to slightly less than 1000 RPM and then slowly drop back to 750 RPM. This 10 - 15 second cycle will repeat over and over until you shut the car off.

A 500 RPM variance is one hell of an accessory kicking on and off, and it does not do it abruptly like an air conditioner compressor clutch but rather "oozes" from each RPM to the next.

Note that when the air conditioning compressor clutch engages and disengages there is a noticeable click, a minor change in RPM and it happens no matter what position the gear selector is in, and will happen even if the air conditioner is turned off if the heater controls are in any of the windshield defogging positions. I became familiar with this phenomenon in my first air conditioned car ... a new 1973 Pontiac Grand Prix.



Given that I have owned cars for over 50 years I believe I can answer 'Have you guys driven literally any other car?" in the affirmative. Given that I have never had a car that exhibited this type of idle I find the FR-S behavior strange. Examples of cars that I have recently driven that do not exhibit this behavior includes the new Camry I used while they had the FR-S in for diagnosis, the wife's Yaris, either of my MR-2's, our Toyota truck, the neighbors Toyota truck, the other neighbors Dodge Ram, the son-in-laws Ford truck, ... but that is only in the last 6 month.

Anxiously awaiting your explanation ...

I can tell you my '13 BRZ does NOT idle like than..even with the AC on. Is it a sign of a problem or a future issue with the car? Can't tell you.

[fatalelement]

My Camry did it, my dad's Hyundai did it, my mom's Odyssey did it. If it doesn't damage the car and many, many people have it I think it's less of a problem and more of "something that it does".

Edit: like crickets.
Sent from my HTC One_M8 using Tapatalk

[jacjac3]

There is a ECU update for this issue with 2013 BRZ. Just take your car in. I did it and my car no longer has RPM fluctuation.

[86Tony]

How many people.has this problems with 2015 models

[Tcoat]

Originally Posted by 86Tony

How many people.has this problems with 2015 models

None! It was an early model problem that was fixed. If you read all of the posts you will see that other then a couple of people that expect a rock solid idle from a boxer engine all the vehicles were early 13s.
The idle does go up and down but it is a normal function of a very precisely computer controlled system.
If it is dropping so far that you are stalling then you may have a problem that requires service but otherwise don't worry it is perfectly normal.

[86Tony]

Originally Posted by Tcoat

None! It was an early model problem that was fixed. If you read all of the posts you will see that other then a couple of people that expect a rock solid idle from a boxer engine all the vehicles were early 13s.
The idle does go up and down but it is a normal function of a very precisely computer controlled system.
If it is dropping so far that you are stalling then you may have a problem that requires service but otherwise don't worry it is perfectly normal.

Thanks man that makes me feel better. I just picked mines up today and starting reading and it got me worrying.

[HotLavaChick]

Originally Posted by 86Tony

How many people.has this problems with 2015 models

me. i should post the video. idk where to host it though. but i drove it off the lot and as soon as i went over 100 miles it started doing it. pisses me off.

[86Tony]

Originally Posted by HotLavaChick

me. i should post the video. idk where to host it though. but i drove it off the lot and as soon as i went over 100 miles it started doing it. pisses me off.

Please do post the video, I have 60km on mines so far. what is yours doing and is it content.

[Tcoat]

Originally Posted by 86Tony

Thanks man that makes me feel better. I just picked mines up today and starting reading and it got me worrying.

That happens a lot on here!This is an absolute treasure trove of knowledge but that can be a double edged sword!
It is waaaay too easy to read something on here and think "hey maybe I have that" and create the symptoms in your head.


Just a friendly heads up:


You will hear weird noises you never heard before in other cars - RWD + Boxer engine + almost no sound proofing = strange sounds


You will probably have a noisy fuel pump (crickets) - There is no guaranteed way to change (not "fix" but change it isn't broken) this no matter what some may say. There are things you can try but there is no one method that works for all. Do not take the time or effort to get the pump changed.


Much (if not most) of the issues and Service bulletins that you may read about here were only applicable to early to mid production 13s. These problems were fixed way before yours or even my car (14) were built.


If you do think you have an issue check and see if it is already on here someplace - If you can't find anything then ask, but remember that "my car makes a swooshing noise when I start it" doesn't mean squat to anybody. Also keep in mind that there are a lot of experts on here but there are also a pile of people that think they are but are full of crap! Verify anything you find out through another source or be very sure you trust what you are told.


And above all remember it is a car and as sad as it can be shit happens!