Afr Help!!!!!

[eastcoastS14]

ok so my car has been in my driveway for about 2 months just sitting I couldnt get into it/ start it long story.... but any way just got it started and my AFR is at 16.2 or higher at idle when i step on the gas it drops down to about 15 something is this a problem?? what should i do please help because i dont want to take it out and destroy my engine

[punxva]

give us more information, like mods and such

[eastcoastS14]

engine:
-rebuild stock block,new rings,bearings ect..
-apexi head gasket
-mild port and polish head
-nismo plugs
exh/turbo:
-ss auto. 38mm wastegate
-custom made top mount manifold
-t3/t04 .63 ar 57 trim stage 3 wheel w. v-band exit
-hallman MBC
-v-band 3" down pipe
-3" exhuast n1 style
IC/Intake:
-300zx maf
-custom intake pipe
-phase2motortrend IC w. custom IC piping
-HKS Filter
-HKS BOV
-samco hoses
drivetrain/suspension:
-nismo motor mounts
-phase2motortrend sub frame bushing
-clutch line
-s14 tranny
-ACT 6 puck sprung hub
-s14 viscous lsd
-5 lug
-300zx brake MC
-skyline R33 GTR 4 pistons calipers(front) stock calipers(rear) also stainless steal lines
-front also has cryo treat slotted rotors
-17x9 +15 w. falken 451 245/45/17(front)
-17x10 +12 w. falken 451 255/45/17(rear)
-D2 coilovers
cooling:
-koyo rad
-samco hoses
-pivot rad. cap
-coolant reservoir
-remote relocation oil filter
Interior:
-sparco fighter seat
-aem uego a/f meter
-hks egt
-hks water temp
-hks oil pressure
-mines LCD boost meter
-DSG delrin shift knob
-Tomei steering wheel
-RS Enthralpy ROM tune
Fuel:
-deathwerks 740cc inj.
-walbro 255lb pump
-sard regulator w. guage
exterior:
-SARD tow hook
-new paint
-pulled rear fender
-silvia emblem
-silvia front grill

[eastcoastS14]

^^ just got back in my car and my afr is down to like 17 and went all the way down into the red ( its an AEM gauge) its on the last red line and the AFR is going switching between 17 and -- at idle some one please let me know whats up

[johngriff]

The issue is obviously your ROM tune. You cannot change your A/F issues, without re tunning the car. You NEED to buy an engine management system to make changes to the AF/R.

Get in touch with me about EMS systems.

John
AIM: RPSport John
Phone: 562.489.5016

[punxva]

yea its most def the tune, just keep it in the driveway until u can get that shit figured out, dont risk your motor

[eastcoastS14]

ok problem is that it was running fine before...last time it was running the AFR was normal...then the battery died and its been sitting and now that i got the battery jumped and turned it back on the AFR is all screwed up

[bardabe]

you need a tune according to my master "how to tune EFI systems this is the ratio details"

6.o rich burn limit (warm engine)
9.0 Black smoke bellow power
11.5 Approximate rich best torque at WOT
12.2 Safe best power at WOT <---- this is what you want
13.3 approximate lean best torque
14.6 Stoichiometric AFR (chemically Ideal) <--- this is what you want for Low throttle setting [cruise]
15.5 lean cruise
16.5 usual best economy
18.0 carburated burn limit
22+ ecc/EFI lean burn limit.

[eastcoastS14]

ok based on this then it looks like the 15-17 AFR sitting at idle is ok and the AFR clearly drops toward 14 and lower as i step on the gas so im guessing that when i drive it should drop to the normal range.... it that right??
looking like 17 is right about at best fuel economy so i shouldnt worry about my engine leaning out as long as it doesnt go past 18 correct??? or did i get this completely wrong?

Originally Posted by bardabe

you need a tune according to my master "how to tune EFI systems this is the ratio details"

6.o rich burn limit (warm engine)
9.0 Black smoke bellow power
11.5 Approximate rich best torque at WOT
12.2 Safe best power at WOT <---- this is what you want
13.3 approximate lean best torque
14.6 Stoichiometric AFR (chemically Ideal) <--- this is what you want for Lowthrottle setting [cruise]
15.5 lean cruise
16.5 usual best economy
18.0 carburated burn limit
22+ ecc/EFI lean burn limit.

[johngriff]

It sounds like someone got scarred staring at their gage too much. Time to datalog the wideband while driving.

[bardabe]

Originally Posted by johngriff

It sounds like someone got scarred staring at their gage too much. Time to datalog the wideband while driving.

what he said.

[GSXRJJordan]

all those mods and you're posting up on zilvia with half the info (or less). I dont understand how a previously "working fine" Enthalpy tune (which are rich anyway) turns into a piston-and-valve-hating lean machine just by sitting with no juice, unless something went electrically wrong in the ECU... then again, I've never seen an ECU start the car if it was damaged/inop, so hmmmmmmm. More info!

[steve shadows]

Originally Posted by bardabe

you need a tune according to my master "how to tune EFI systems this is the ratio details"

6.o rich burn limit (warm engine)
9.0 Black smoke bellow power
11.5 Approximate rich best torque at WOT
12.2 Safe best power at WOT <---- this is what you want
13.3 approximate lean best torque
14.6 Stoichiometric AFR (chemically Ideal) <--- this is what you want for Low throttle setting [cruise]
15.5 lean cruise
16.5 usual best economy
18.0 carburated burn limit
22+ ecc/EFI lean burn limit.

the dynamics of the change with the type of fuel you are using

[steve shadows]

either way if your running around on 91 octane for example your afr should be in the 11:1 range. If your using 93 octane it should be more like 11.5:1 for safe and still pull out some timing etc.

If you are able to look or have someone look at the guage while your driving full throttle say a third gear pull down the FWY etc or on a DYNO which would make this a lot easier and safer, you can see what it is under stable boost and full throttle position, that would help.

AFR is supposed to be lean ie, 15-16 at idle in some cases depending on if your ecu was tuned for specifica cam setup etc.

hope that helps.

[eastcoastS14]

yeah that does help ill take it for a drive and have someone watch the gauge and post the results