cbustuner

I know this isn't a hardware or software related issue,but more due to these being the being the biggest injectors I have ever worked with ( fuel injector clinic low z 850cc injectors )

When trying to tune my idle to 14.7 or leaner the car will pop and miss ALOT.It will drive fine threw out the rest of the rpm range and in boost but at idle it will miss.When i richen the mixture up to around 13.5-13.8 it will idle smoother and steadier and around 850 rpms.All around it idles better when it's richer then 14.0.I have tried a few things and nothing besides that works.Tried battery offsets,checking my distributor timing,boxing my ignition colummns in,checking for vacuum leaks and fixing an exhaust manifold leak.I know my 3 inch open downpipe doesnt help the missing/poping problem but when its richer then 14.0 it barely pops and is soo smooth

Anyone have similar issues?What size injectors is everyone else running and what is your idle afr?

zex_cool

do what the motor likes. if thats 14.0's then leave it there. my old setup idled at like mid 13's or something. anything leaner it would jst pop and studder like crazy.

cbustuner

thats what im going to have to do.I did some logging today and when its around 13.5-14.0 its around 1.60ms and 1%- duty cycle.Im thinking maybe the injectors don't like going any slower

0xenocron

Playing with your Injector OFFSET or Battery Tables is what will really get you idling at a more normal AFR.

I like posting this link as it explains a lot:
http://www.yawpower.com/inject....html

cbustuner

I hoped you would chime in...

I tuned my battery offsets using a post you made on pgmfi.org I read a long time ago.Start the car,warm it up,turn everything on ( heat lights,hazards,radio,everything) and then try to keep the afrs as steady as possible by adjusting the tables (higher number = more fuel,lower number=less fuel) .Being able to log advance tables in eCtune is realllllly useful.

cbustuner

I busted out my volt meter and im getting 2.3ohms at each injector.I know fuel injector clinic injectors are ball and seat and so are msd's and precisions which are also around 2ohms so Im going to save my current map and start over using eCtunes included pte/msd injector battery offset tables and hope they have similar enough characteristics (They look exactly the same) and then further adjust the tables from there.

Gas is to exspensive for me to want to idle at 13.5 afr unless I have too

zex_cool

on my current setup i used the fic 650cc injectors with eCtune's battery offsets for the precision 680cc injectors. worked like a charm. no popping, studdering or anything like that. too bad i cant say the same about the 1k's that i have in right now.

blackeg

i just put some 880's in tonight. my idle is currently in the low to mid 13's afr wise. i had it as lean as low 14s before it would run like ****. it actually idles best in the 12s, but i didnt want it that rich, so those 13s became the compromise i made. ive also got my target idle set at 1000 and my iacv duty cycle at + 25 percent in the rtp settings

cbustuner

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by blackeg &raquo;</TD></TR><TR><TD CLASS="quote">i just put some 880's in tonight. my idle is currently in the low to mid 13's afr wise. i had it as lean as low 14s before it would run like ****. it actually idles best in the 12s, but i didnt want it that rich, so those 13s became the compromise i made. ive also got my target idle set at 1000 and my iacv duty cycle at + 25 percent in the rtp settings</TD></TR></TABLE>

Thats pretty much exactly like mine is with my current map.Around 13.5-13.8 its smooth and steady.I even got it to idle at 850rpms.

Im still going to try redoing the offsets on a fresh map,If I can't then it looks like im stuck with 13.5 for awhile with my current map.It just sucks because I have to redo some of the street tuning I already did,but it will be worth it if i can get a leaner idle.Also doesnt hurt learning more.I have nothing but good to say about eCtune.

In eCtunes preset battery offset tables the closet thing to the fic 850's are msd 750 and pte 1000's and those offsets are very similar.

non-VTEC

im running into the same issue with my rc750cc injectors. been running them for over 3 years and it always likes to idle richer than what is considerd normal.

cbustuner

anyone else have any insight or the same issues?

BadWay

have you tried messing with the ignition timing? i've had a couple cars that wouldn't idle with more than 10-12 degrees of timing, while some will idle smooth at around 20-24 degrees. some engines are just plain picky. my engine idles at about 16:1 afr and 16 degrees @ 1000rpm with 1000cc injectors perfectly smooth. timing tables below 1000rpm are about 12 degrees. i usually start by getting the afr where you want it, then try adjusting the timing to smooth it out. HTH

cbustuner

I'm going to give that a try. I didnt touch the ignition timing maps around the idle area. it's at 16.50 degrees which is stock for my motor at 750 rpms +/- 50.

97luder

Were you able to improve on the AFR and run the car leaner at idle? I would imagine it's not possible simply because the injectors are too large to idle smoothly. I'm running Precision 880cc on my MR2 turbo and I can get it to idle smoothly at about 13.8 afr. Anything higher and the motor starts to hunt like mad.

Does the eCtune let you adjust the Air Temperature Correction Curve?

-kl

ralph11sec

i guess its pretty standard,
i have my 880s idle at high 13s NO a/c, if with a/c it goes to 14s with no problem. anything leaner will make it go.
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big injectors = idle rich
at least majority of us