16.7 at idle why lean?

[shay4g63]

So I've been having some troubles getting my dsm to be happy at idle.

she runs 12.6-14.2 all day when in boost which i'm happy with

but at idle she says she is around 15.4-16.7.

mods are
50trim 20g turbo
2g maf
fmic with hard pipiing,
750cc FIC injectors
255 walbro(not rewired)
stock fuel rail and fpr
safc2
narrow junk band
boost gauge
And borrowing a buddys wide band

Now at idle on the low throttle postion from 800rpm-2000rpm it's at 0%.. after that i have to pull fuel but yet i'm STILL rich.. doesn't blow black smoke at idle or anything, it's just od!

 

[snowborder714]

Part of your problem might be that an SAFC isn't really a good idea to use on injectors larger than 660cc.

 

[Dert]

So I've been having some troubles getting my dsm to be happy at idle.

she runs 12.6-14.2 all day when in boost which i'm happy with

but at idle she says she is around 15.4-16.7.

mods are
50trim 20g turbo
2g maf
fmic with hard pipiing,
750cc FIC injectors
255 walbro(not rewired)
stock fuel rail and fpr
safc2
narrow junk band
boost gauge
And borrowing a buddys wide band

Now at idle on the low throttle postion from 800rpm-2000rpm it's at 0%.. after that i have to pull fuel but yet i'm STILL rich.. doesn't blow black smoke at idle or anything, it's just od!

If your on pump gas then 12.6-14.2 in boost is running lean as well, you should be aiming for around 11.1 afr's. Having a lean idle isnt really a bad thing, it's your cruise and wot you need to get in check. Cruise you should be around 14.7 and wot 10.8-11.1 area, again, if you are on pump gas which I assume you are judging by your mod list.


Sent from my iPhone using Tapatalk

 

[V12 Killa]

Part of your problem might be that an SAFC isn't really a good idea to use on injectors larger than 660cc.

Pretty sure this why. But My WB would read 18+ and came to found out my throttle cable was too tight. Just throwing it out there.

 

[shay4g63]

no smoke..no lobbed idle, no overheating. plugs looked good

 

[AZN29]

I have this same problem, I wonder if the o2 is going bad...

 

[shay4g63]

Well, it says it's lean at idle and cruising.. but if i give her some throttle(12-20%) she goes to 14.2-14.8 ... Put what throws me off the most even if the 02 was going there larger injectors.. they should still be running rich.

I'm throwing my old FIC 650's in today see if that makes a difference.

 

[Dert]

Like Brian stated above, you have 750 injectors and are using SAFC wich can only handle tuning up to around 650cc injectors. You are unable to get a correct tune on your 750's wich is why you are lean from idle to WOT. (I`m saying WOT because you stated she runs 12.6 to 14.2 all day under boost and your happy with that wich you shouldnt be because 12.6 to 14.2 at WOT is extremely lean, you should be happy with 10.8-11.1) I would personaly scrap the SAFC and get ecmlink and keep the larger injectors, but to each his own.

 

[shay4g63]

Dert thank you. I put the 650cc in and no change? same crap... I'm getting a ecm v3 here soon.. if anyone in the edmonton area is familiar with tunning this... pm me please!.. I'l gonna keep the 750cc in as it's the same problem but we got it down to 10.8 under wot and 11.2 under 75% throttle.

do you need a laptop with a cd drive to load the v3? I only have a net book=no cd drive

 

[Dert]

Dert thank you. I put the 650cc in and no change? same crap... I'm getting a ecm v3 here soon.. if anyone in the edmonton area is familiar with tunning this... pm me please!.. I'l gonna keep the 750cc in as it's the same problem but we got it down to 10.8 under wot and 11.2 under 75% throttle.

do you need a laptop with a cd drive to load the v3? I only have a net book=no cd drive

Good call on getting link, you should be able to tune your injectors fairly easily with it. Having a lean idle wont really cause any harm because there is virtually no stress on the motor, it just means you will burn less fuel idling . Good to see you got your wot in line as that is where it counts. As for needing a cd, they will send you a disk but you can get all the download links off ecm site as well as a good amount of info and a few demo videos to help give you an idea on how to set up your base tune. Heres a link to the downloads if you need it...

ECMTuning, Inc.

 

[shay4g63]

sound good.. i will be doing some reading.