I really wish I knew how to answer that :/

I’m so not smart when it comes to these. I rely on my shop, seb, and you all :)

Anyway you can tell me how to figure that out?

Any codes? Looks like a vacuum leak, or you need a re-tune because ur leaning out on fuel trim 4 a reason.

No codes.

Runs at 14.7. Except for this slight dip. AFR will go from 13-15.5 during the dip or prior to the dip.

Got retuned by seb 2 months ago (issue was happening then as well) because of new fuel pump and ecutek went to v5.

Here's another one today.

This is what usually happens once or twice during the first 5-10 mins of the drive...



www.youtube.com/watch?v=XC_BoHgy2jA


I tried embedding this video, but for some reason - it keeps coming back with a play error.

:tiphat:

You’re a saint.

Thanks.

So I’ll just throw in my experience as I’m similar setup with aem pumps in radium kit running 51 psi, stillen intake, stillen exhaust, Bosch ev14 550cc injectors tuned by seb and on e85 and my idle is completely fine so I’d say just a hunch but less to do with running e85 on a z and more to do with the 1050 injectors. That’s a lot of injector for an NA car anyway and from what I’ve ever heard and read is the larger the injector the harder it is to get a controlled idle as that’s where the engine is pickiest and the hardest point to control a large injector.

That was my thoughts too. Too big of injectors. That's why I asked about the injector dwell time. Dwell at WOT should be around 80 to 90%. If it's more, the injectors are not big enough and will lean out the mixture. If it's less, The injectors are too big and will cause idling issues.

Ok. So that narrows it down a bit.

I’ll talk to seb - maybe I need smaller injectors.

Thanks guys.

It is all in the tune. I run 1700cc injectors and have no issues. Do you need that large of an injector NA. That would be a no.

Yeah, I’m not having the same issues with 1050cc NA. The car runs smooth for me.

I guess I meant to say it’s not impossible just much more finicky and needs tighter controls at idle as well as really good injectors and for an NA engine not necessary so why bother with the headache. Known others with high boost 4 cylinders that require larger injectors and most have always noticed a decrease in idle stability after but have to deal with it as it’s needed for high boost levels and no way to do a multi injector setup.

You could do a multi injector set-up. BUT.......how much MONEY and time do you want to throw at it?

It is always NA at idle. It just requires more fine tuning for the tuner with larger injectors.

So if you guys were me, do I go back to seb and ask him again?

He’s already aware of what it’s doing. Said tune looks solid / maybe it’s the WB O2?

Again it’s not stalling or anything - it happens 1-3 times in the first 5-10 minutes of driving and then it’s like it learns and adjusts fine. AFR is perfect other than when this happens. I can probably live with it. Just wanted to make sure it isn’t going to cause a future issue.