Mach929

iTrader: (3)

my setup:
unmolested 1.6 maf
305cc supra injectors, cleaned a tested
emanage blue set for 205/230 injector correction.

LM1 says on the cold startup(about an hour after i got home from work, so not totally cold) that i'm around 17afr and then as it warms up it settled to 15.7afr. why would warming up get richer and not leaner?

I've been under the assumption that with this setup i would be idling rich, which was also why i thought starting sometimes was a pain and idle sucked and fuel economy was garbage.

Any ideas, unfortunately i can't get into my emanage since i use my fathers laptop and he's in florida.

Stripes

iTrader: (8)

Did you do an open air calibration?

Ben

iTrader: (33)

I've always been lean at idle no matter what. I've been through a few afm's, injectors, removed BOV. Always close to 16:1 at idle. (Except for when I had the EMU and 550s I tuned it a little richer at idle because it felt smoother around 13:1.)

Mach929

iTrader: (3)

yeah i did do an open air calibration, i'm not really sure about this one. maybe burn the car, it's heavily insured

Braineack

iTrader: (62)

with just my oem ecu and "tuned" oem afm, i would see a 14.7 AFR, unmolested afm and id see a 12 AFR at idle....

MiataNuTca

I'm lean at idle as well......I've just learned to live with it. I'm around 15.5:1....heats up the engine quicker and is more fuel effecient, so I don't mind so much. Could be the IAC (Idle air control) on our cars has gotten too old.

Exhondaman

My AEM Uego read low 15's before the greddy install and now it reads 16.5ish. The question now is, "Why is it bad to run lean at idle?"

PAT!

iTrader: (1)

To lean can hurt tip in but without load there isn't any real danger.

The car gets leaner as it warms because there is more fuel during cold start, to drunk to collect my thoughts as to why but Iknow that lubrication is one...

Braineack

iTrader: (62)

im going to be specifically tuning lean at idle

....but since you have the LM-1, maybe you'd want to see what others tailpipe readings are and see if it's close?

Ben

iTrader: (33)

Pat, my car does the same thing, its lean at idle, and idle only. Over 1000 rpm, A/F dithers about stoich. At idle, it settles in at around 15.7-16:1. Figure it can't hurt nuthin.

akaryrye

iTrader: (5)

Scott, I was unable to get a stable idle at anything leaner than 14:1 with my 550 rx7s. Im interested to see how that works out for you.

Mach929

iTrader: (3)

playing with it last night i found that if i tuned for ~14.7 at idle, it would cruise really rich. I can't drive with the lm1 yet becuase i was only using the o2 bung about 3 inches from the turbo, i don't want to overheat it. So i started where the lm1 said it was 14.7 at idle, then i drove cruising at light throttle and kept leaning it out till the narrow band was happy during cruise and still idled acceptably so it's probably still pretty lean at idle but not as bad and seems to start easier, also put in a brand new nb o2 sensor which seems to help.

MiataNuTca

I have a theory about this.....stock IAT's are taken from the afm. The stock computer makes it's own adjustments based on intake temps. Since the AFM is so close to the turbo, it may retard things too much causing abnormal idle conditions. I'm wondering if I can relocate the temp sender to somewhere after the intercooler.

magnamx-5

iTrader: (7)

just get a MSPNP and run there ait problem solved.