Brz doesn't like to idle
 

Hi guys,
Recently went in for maintenance, swear this is like the third post I've made in a month. What happens is after I drive off after I've given it time to warm up, when coming to a stop and putting the car to neutral the car dies. It doesn't happen every time maybe 40% of the time. There are some drives it doesn't even come close to stalling. The problem seems to happen when A: it's hot outside(90F) and/or B: I don't idle for like 10 minutes. Currently in the tuning process, I'm on the second tune from my tuner. I've emailed him and am waiting for a response. I also seem to be running a little lean (14.7-15.3 AFR) at idle. Fuel pressure being reported by the flex fuel kit is at 55PSI and I'm running 93 octane. Other than this problem she runs great.
Mod list(changed from since working):
Dw300c and id1050x injectors
Flex fuel kit
Boost controller
EVAP disconnected, hoses clamped
Spark plugs
Belt replacement
New intake filter
Cam plate replaced
2017 intake manifold

Any suggestions are greatly appreciated!

Do you have a custom tune? If so, I would have the tuner take a look at it. There are multiple things there in your list that change dynamics.

FA20 is pretty notorious for poor idling.

But since you've reached out to your tuner, you're in the right direction.

Personally I found slightly improved idling after I swapped out my dying battery, ignition coils, and spark plugs and Chevron/Shell gas.

After some hard long use, it can still have a bit of a rougher idle still but better than before.

Let me guess.
Ecutek racerom and US base tune, like it ends with the letter C...




Bug. I talked about it often, no one ever cared about it, so there is no fix for you unless you force your tuner to convert your tune with an EU base tune... thing that he will not do it also because he's not aware of, and your idle will always suck

not really. once it settles and only DI is used for idle, is pretty rock solid


Who has idle problems, has actually tune problem

:confused0068:No, its notorious. You can google it yourself, but here's an example of just how common it was (large car publications were publishing articles about it).

https://www.motortrend.com/news/we-h...g%20conditions.

https://www.autoweek.com/news/a19712...ay-fault-lies/

https://www.autoblog.com/2012/10/05/...e-ecu-reflash/

https://www.cars.com/articles/2015-2...1420683185723/

1200 hits:
https://www.google.com/search?q=frs+...=2560&bih=1307

it s notorius but i ve retune 70 cars since 2018 and no one has idling problem.. it s fixab le, just that most people can t find the right solution

stock tunes and ots tunes Have idling problems btw. So do every custom tune that has idle set like them.

Do flash new tune when the engine is warm. And search "subaru idle relearn".

You probably have an Asian base tune as your custom tune, with no bugs

Those guys have US base tunes that have a bug with ecutek racerom that will force them to use PI during idle.. they ll never get a steady idle no matter how they help with the relearn, specially with big injextors

OK so your first 3 links are from October 2012 so not sure how many people actually had an issue. They all are just clickbait's parroting each other anyway not even independent investigations. The issue was fixed before 99% of the cars wee ever sold.
Your 4th link is an issue very specific to one model year with AT only. Again it was fixed with a simple update.
Your 1200 other hits mostly start with "I have an XXX turbo or tune and have idle issues". Pretty much supports they are a mod and tune related problem. Oh and of course there are the many many "Happens when the A/C is on" which is perfectly normal but some people refuse to understand that.

Idle issues are not common on unmodded cars after the very first batch. If somebody with a tuned car has this issue they need to check the tune not ignore it and say "OH these engines all do that". They don't.

The only time my idle gets weird is when the ac is turned on/off

I have never had an idle issue with my bone stock '13. It still has the second ROM, the one where they removed the DI seal-blowing feature.

This pretty much, speaking from experience...

while it is perfectly normal, there is still a way to tune this out and minimize it

Every twin I've seen experienced some from of brief rough idling dip, even after the "fix".

I will confess I haven't spent as much time with the newer models after 2015, but I have still seen it in every twin I have looked at - including the occasional newer models up to 2018. I haven't personally looked past 19 models.

It also could be because I'm in California - which mostly sells only up to 91 octane. May attribute to a roughly idle. And yes, a tuner should be able to fix it.

Can you explain this a little more? What do you mean by C and US base tune? To clarify, I am turbocharged and had a previously working tune with Ecutek with no idle problems at all.

I'll give that a try, will reply with the results later

Yeah, maybe that's would explain why after idling for 5-10 before driving solves my issue too

Work with you tuner, Also since you have done the intake manifold double check for intake leaks.

update:
still not solved, also pulled code 0463 so im gonna work on that.
none of the above solutions have worked, and my tuner went on a vacation apparently and has a bunch of cobb users trying to get their flex tunes up. maybe ill get a reply this weekend.

is there any chance the boost controller replacing the EVAP has any effect on this? EVAP system and hoses (clamped) are still there, just not powered.

do you have a log ?

Please make an account in datazap. me , upload it and link it to us

https://datazap.me/u/toughguy39/stalling

As requested. Log file 23-23-44 showcases the issue. started data log, replicated problem and ended it. It also appears the issue only occurs if i go to neutral under 2-2.5k rpm.

https://datazap.me/u/toughguy39/stal...zoom=1217-4841

do you see that? PI switching to 100% all the time when you leave the throttle?

that s the bug i was talking about

you never gonna have your car idling good and smooth
unless your tuner force-upgrades you and totally converts your tune to an euro tune
that brings some problems, 1) i m almost sure your tuner isn t aware of this bug and doesn t carr, and he doesn t know how to force-upgrade you 2) by converting to euro tune and get away with the bugs, the fueling will be quite off, so you will require a complete new retune

If I'm understanding this right, since this is a bug within the ECUTEK software, why can't they fix it and code it properly?

it s a bug in the racerom patch specifically, from around racerom 10.1 till the newest 12.3, it s present..

for the question you asked, you should ask ecutek directly and why they don t provide a fix , i don t work for them :)
They reverse engineer the tune from the stock directly, they do not have any help from Subaru, they find what they find. I told them via email about the bugs afflicting US tunes patched with racerom, they don t care about this car anymore.

they are based in England, and they own a Euro car.. they always defined very well the euro tunes, not so much US and asian tunes

I keep writing in this forum that US tunes are bugged since years when patcher with ecutek.. but nobody listen to me or believe me, so unless you do something against it, you will have a bugged and not smooth tune forever.. as HUNDREDS of other americans people in here that have no idea of what s happening in their car and trust tuners like Delicious

Well, SOL i am I guess :/ Didn't want to dyno tune since the closest reputable dyno is a 3 hour drive, maybe that's in order. This is something a dyno could easily adjust yeah?

No. why should a dyno fix it?

you need to force-upgrade to euro tune. Or downgrade to very old and not so good for turbo, racerom 9. No other way. that means you need to do a full retune with a reliable guy. I m one of it :) or like Zach at CSG should be aware of this

i mean, if this tuner with a dyno then put on a US tune again, the bug will still be there, and probably will just not notice/ignore it and you are at starting point, with less money

Many tuners don t even know how to force upgrade our car

Also your idle and stalling problems are exacerbated by your super huge injectors, other that they seem unnecessary ( i don t use E85 but i use since 3 years stock 228cc injectors with 1.05 bar of boost) they can t inject precisely or short enough for 100% Pi idle

People with stock injectors tend to notice less this bug because it doesn t stall with stock injectors, it just runs shitty and they ignore it thinking it s all good

Crystal clear explanation. What a damn shame! This is precisely why I haven't yet touched my stock ROM. I feel like I would have to approach your level of understanding before fiddling with it. I deal with fully documented systems all day long. I think that if people really understood the nature of this kind of reverse-engineering, there wouldn't be so much blind trust. There are MANY areas still known only by the original authors.

Tables are relatively easy to find and manipulate. Functional relations? Nested dependencies? Blah blah blah... Nope. No way.

but they did a good job at ecutek, with plenty. of defined tables, a bit more than those from open source 's guys.

The real limitations come out when you try something exotic with custom maps, some things like accelerator modification through them can easily break things and trigger a dangerous limp mode with unresponsive pedal for example... or in this case the racerom patch that doesnt work perfectly with US tunes because obviously, when they ported the patch from initial euro tunes to the rest of the world that has actually some differences in the Ecu logic, something was off and somehow it hasn t gotten fixed yet...
they have no complete control over the oem tunes, that s right

still, the fact they filled empty spaces on it with A LOT of new non original tables and 16 new separated custom maps that work so well with the oem tables in most situations is great

When I've learned to reliably get back to full stock. I dunno, man. Fucking black boxes, goddammit. *shakes fist*

same here, I didn't face any idle issue with my car

Problem resolved: faulty BOV