3min3m2

Ok I'm trying to figure out my idle characteristics.

These have occurred after:
Turboing(about a week later)
Checking for boost and vacuum leaks

Now here is my interesting characteristics:

idle RPM around 700 MAX. generally around 650-680(per E-manage)

car does not feel significantly rough, especially W/O torque dampener

Car will occasionally lean out during idle. AFR drops to 17 slowly, then comes back. Appears to be random, but only occurs after deceleration(but so does idle..so no way to tell)

Car does not like to run when the AFR changes, kinda gets a rough idle, but the ECU eventually fixes it, going rich then coming back to 15.3, where it was before turbo

Idle Vacuum is 20-21. Right where it was before turbo. Idle was not different at all before turbo, i believe i do not have vacuum leaks, unless right at gauge not really effecting engine running.

Here is what I am thinking...

Clean Throttle Body?
new Primary o2 if nothing else?

Ideas?

Now

ESEMRFOZZ13

could be your tune on the emanage, mine was shooting for the stars to a whopping 16.5 afr

deathbyc4

You should move this to the forced induction section. we need more details...PSI? fuel setup? exhaust setup?

3min3m2

I put it in here due to it not seeming to be boost related...but if a mod would move it I have no objections

PSI-6
Fuel-440 inj with the kit.
Exhaust-Megan s-pipe and drift spec. Checked for leaks as well.

I dont have anything in the emanage set to affect the idle other then the injector signal change from the stock ones to the new ones

I have datalogged it, and noticed the injectors decrease .1% during the AFR climb.. but .1% is that enough for 2 AFR increase!?

ESEMRFOZZ13

did this get tuned for your car?

3min3m2

Im tuning it. no tuners for about 600 miles.

really nobody has moved this or has any ideas??

deathbyc4

A return fuel setup would fix the lean idle and help with not having to tune as much. as far as the idle? thats a tough one. what management you running?

3min3m2

Cleaning throttle body helped massively. Also changed boost/vac gauge and re routed vacuum lines resulting in much better idle and running characteristics...

rangerryda

iTrader: (1)

Get a scangauge and check your fuel trims. This was the case with a buddy of mines custom setup. Tune ran great except for idle. Fuel trims were waaaay off but the ECU would constantly keep trying to save it so the revs would bounce way up and down.

ScionFred

iTrader: (1)

I've had the same thing happen several times. Eventually the ECU adjusts the idle LTFT to compensate. In my case it was caused by my LTFT being too far negative. I'm not sure exactly why but with 440cc DW's my fuel trims vary a lot from cold idle and crusing speeds to warm idle. When I tune for 0 LTFT overall I end up with -20% cold idle STFT and +15% warm idle STFT. If the LTFT is -10%, the ECU will only add 20% STFT at warm idle which results in a lean, slightly rough idle.

If you're tuning yourself you really need a scan tool to check your fuel trims. Until then you can try changing your injector correction factor or just add some fuel to the idle range of cells. With the FIC, increasing injector response time seems to help as well.