ECMlink Idle Tuning Issues

[WES_393]

I'm having some trouble getting my idle tamed. Since day one I have had idle surge which was eventually fixed with a new front O2 sensor and some wire doctoring. Fast forward three days of sitting in the car trying to get the idle under control. I've tried simulating narrowband with my AEM UEGO, swapping in the old O2 sensor, I even jumped ahead a tad and used the MAFComp tool to maybe try smoothing out the airflow down low. Nothing has made a difference. So here's my issues now:

- High idle even after new ISC, multiple BLT's, etc.
- Front O2 still gets crazy at times such as ~200 seconds in the log
- Airflow/rev is pretty low
- I can hear/feel multiple misfires while idling even after dialing in the injectors (Denso 660cc).

If some of you more advanced tuners could take a look at my log and let know what to change that would be much appreciated. If you need me to take a longer log or add some things to the captured values I'll do that ASAP and post another log. I noticed my Wideband didn't capture in this log for some reason, but it fluctuates between 14.7 and 15.0. Thanks in advanced!

 

[jpmxrider489]

Did you try adjusting your deadtime or global fuel. Maybe you can try something with compft? Im pretty new to link but I saw no one replied and figured Id give it a try.

 

[WES_393]

Did you try adjusting your deadtime or global fuel. Maybe you can try something with compft? Im pretty new to link but I saw no one replied and figured Id give it a try.

Thanks for the reply. Yeah, I have played around with all the fuel injector settings. Where I'm at now is what it took to get to 14.7ish idle.

 

[dsmpat95]

You need to log ISCpostion.

Let ECMlink do your narrowband sim.

If you can't seem to get you wideband to read right while logging follow this. It will also help set up narrowband sim on LINK. http://www.dsmtuners.com/forums/tun...23359-aem-datalogging-wire-where-does-go.html

You will have to idle your car down a bit.

 

[snowborder714]

Have you made sure there are no boost leaks?

Your AirflowPerRev is really low (.19). It should be higher - around .26. Watch the videos on this page, especially #8 which will show you how to get AirflowPerRev and your fuel trims in check at idle.
ECMTuning, Inc.

I'd start by zeroing out your MAFComp sliders and then watch video #8 and try again.

 

[jpmxrider489]

It seems that your not telling link where your wideband is. Are you using the wideband through link?

 

[WES_393]

I'll log my ISC position and watch video 8 again, but I have followed those videos pretty closely with no luck. I have also done quite a few BLT's, the most recent held 35psi like a rock.

And Link is reading and logging my wideband in all my other logs, just not this one for some reason. I also don't want to simulate narrowband if I don't have to. But if I decide to, are they any good links to setting up narrowband sim? Last time I let Link simulate the narrowband it wasn't cycling like it should. Do any of you find my O2 sensor to be strange? It doesn't look like any of other datalogs I've seen.

Thanks for the help! I'll try to make some changes and post another log here soon.




Here's the log I took today. I started over from scratch and got much closer. As you can see airflow/rev is between .24-.25 and fueltrim is +-2%. I had to adjust the airflow by over 30% at the bottom to get there . Towards the end of the log I tried simulating the narrowband O2 with the wideband and it just make the A/F ratio and fueltrim fluctuate even more.

I noticed my ISC position is at 0, should it be 1? My timing is also around 14* but that could be from the high idle, correct?

 

[edged1g]

An ISC position of 0 means the ECU is trying to close it completely to get the idle down. I say trying because there is no feedback in this circuit so if the ISC doesn't actually close, the ECU has no way to know. An ISC position of zero means the ECU is trying to bring the idle down, but can't. Usually means a boost/vacuum leak, bad ISC, missing or misadjusted BISS or a missing idle switch. ISCposition should be around 30.

idlesurge [ECMTuning - wiki]

 

[WES_393]

^ Thanks for that. I'm starting to suspect a leak somewhere as well. My ISC position was in the 50's during startup and then dropped all the way to zero. I got the idle to come down quite a bit (950-1050) by simulating the idle switch, but at this point I think the issue is mechanical.

I'll try sealing things up a bit more and posting a new log if I have anymore issues.