a cupple of safc fine tuning questions

[AN89HATCH]

I have a cupple of fine tuing questions for safc. For some reason when fist starting my car, it seems to always run ritch like in 11-13 air fuel ratios, untill after about 5-10 min, then it will start to idle in the 14's/ 15's is this normal? this morning my car sorta was bogging out untill i gave it gas for about 10 seoconds then it got back to its ritch cold idle. maby its my walbro fuel pump causing it to idle ritch? also when crusing on the freeway my air fuel ratio goes from 13's to 15's randomly sometimes i see a 16, but that mite be me just letting off the gas. Is this also normal? my last question is about the part throttle boost. I have the car tuned so it runs 11 air fuel ratio's when floored and my thro points are 20-40. My turbo is a t3/t4 i get full boost around 3500rpm should my car be ok on part throttle boost? how do you tune part throttle boost/transiton from vacume into boost?

[Florida240sx]

What kind of a/f meter do you have? I'm gettign the safc figured out. Whatever you lo and hi points are set the safc will adjust fuel according to what throttle % you are at. so say you have. -2 at lo and 2+ for hi and this is at 20% and 40% at 30% throttle it would be 0% Thats what I have understood from reading the book. Anything between your hi/lo points is a ratio. take the average of the 2adjustments and applie it to your curent throttle %

[Jookmasta]

so some answers to ur questions: yes that can be normal pending on what ur fuel pressure is and/or what ur decel settings are. post up what ur fuel pressure is and what ur decel settings are cuz i know my friend had to mess with his fuel pressure (i think lower it) so that at startup, he got normal a/f's. cruising a/f's should ideally be 14s or 15s but its not a bad thing to see 16s. while cruising, u are suppose to run lean (not too lean) as that is what is the saving grace of ur gas mileage. as for ur last two questions, part throttle boost is still boost. u want to still be in the elevens or twelves as part throttle could easily turn into full throttle. and how to tune for this, u just need to have someone in the car with u looking at the wideband while u try to drive with partial throotle and produce boost. let them see what ur a/f's are reading and then u can just adjust the fuel after u do ur pulls.

[AN89HATCH]

yah I have a stock fpr and i think the pump is making it ritch when cold. cause when it gets hot its back to normal. I have a plx m300 wideban, and for some reason my car is always changing air fuel ratio's one day my crusing is perfect then the next day its crusing hella ritch 10's and 11's getting confusing maby its the weather or something

[AN89HATCH]

hmm tonite it was sorta cool out, and my cars check engine light came on, and the car stared to bog then died and did not start untill about 3 trys. I dont understand why its running so rich when cold. I can lean it out, but if i do that once the car gets hot it will run to lean. Also I dont understand why when my motors cold it cruses in 10's threw 12's then after about 10 min of driving my crusing is back at a 14 this is frusterating and makes no sence

[Craving4Boost]

does it affect your daily driving? does it feel sh*tty

[AN89HATCH]

does it affect your daily driving? does it feel sh*tty

it doesnt really affect the daily driving, just for the first 10 min of drivnig, my car drives in the 11's threw 12's then after 10 min its back to normal

[kuramaya]

What Motor are you running? Turbo? What is your low throttle setting at %? Is the DECEL Air setting set? At idel the ECU could be causing it to lean out..You should not worry about adjusting A/F ratio at Idle anyway..unless it is ridiculous. 14 is okay at idle.

edit sorry, see you are in the KAT forum...yeah is your DECEL Air set?

[Florida240sx]

I'm havign issue as well. Can someone please post their dec air settings. To get me close...What gear am I suppose to get the % from?

[kuramaya]

Woah slow down brother..your gonna break something....If you gusy need me to explain Decel Air let me know.. Every car will be different. You should only use the settings if you have to..it is designed to eliminate the need for recirc the blowoff valve...stalling and backfiring can be elimnated. I can hook something up if you need it...I have it posted somewhere on another forum...but I am not familiar with the KA and how your MAF/ECU will react...should be the same or close

edit - you should be in neutral when setting the decel air..has nothing to do with gears

[AN89HATCH]

What Motor are you running? Turbo? What is your low throttle setting at %? Is the DECEL Air setting set? At idel the ECU could be causing it to lean out..You should not worry about adjusting A/F ratio at Idle anyway..unless it is ridiculous. 14 is okay at idle.

edit sorry, see you are in the KAT forum...yeah is your DECEL Air set?

my turbo is a t3/t4 my throttle points are 24/45 dec isnt set since im rec the bypass valve. does it really matter if my car idles in 12's /13's? I think my whole problem may be since i tuned my car on a cold nite, and ive been driving it in the hot days so thats probolly causing it to run rich most of the time i cruse my air fuel ratio jumps from 13's to 14's to some imes 15's, the idle will be from 12's to 14's but my gas milage donst seem that bad should i even worie if its ruing 13's when it should be running 14's? Also i tuned the car when the motor was warm on a cold nite, am i suppost to tune the car with the motor cold on a cold nite? or is it ok to tune at operating temp on a cold nite?

Florida240sx my car also ran bad with the open bov, once i rec it, it ran like a stock turbo car

btw: kuramaya "edit sorry, see you are in the KAT forum..."

i dont even know why i posted there, i get so much moore help on here lol

Modified by AN89HATCH at 10:17 AM 8/1/2005
Modified by AN89HATCH at 11:01 AM 8/1/2005

[Florida240sx]

You need fuel man.Don't need to be boosting that high A/F. As for idle it doens' really matter.Only disadvantage I see is burning gas that doesn't need to be burned.Also depending on how much it may foul your plugs.K I'll go set my dec now. you set ne1 and ne2 % for your throttle points correct? 1000rpm/16000rpm What abotu the top one.Heard set the % above both of them...

[AN89HATCH]

You need fuel man.Don't need to be boosting that high A/F. As for idle it doens' really matter.Only disadvantage I see is burning gas that doesn't need to be burned.Also depending on how much it may foul your plugs.K I'll go set my dec now. you set ne1 and ne2 % for your throttle points correct? 1000rpm/16000rpm What abotu the top one.Heard set the % above both of them...

oo when im in boost, its perfect in 12's then 11's, im talking about my crusing air fuel ratios

[kuramaya]

This was Originally wrote by the Site owner of Zeroyon Forum Hugh. I have tweaked it a bit to make it easier to relate to my set up. I am not sure how the ECU/MAFS on the KA setting the SAFC will work since I havent done it...but this is how I Set The DECEL Air setting in my SR20DET. The only thing different is the NE point possibly. For you standard settings for NE Points, Some people set their 1st NE Point at 1,000 this makes no sense...you do not need to use this point as you are near or at Idle..save your points for later when you are building/Under boost and need to add or remove Fuel. The DECEL points are quite easy to set, There are only 2 of them. I have absolutely no Stalling Issues since I have set the DECEL air..It is a great feature if you wanna run Atmospshperic and it is one of the Main Rasons I bought the SAFC. The Power FC does not have this feature either. Here is how to set it:Start when the car is cold. Overnight sitting is what I reecomend Turn key to accesoory on so the SAFC comes on, go to DECEL air settings. Set throttle to 1%. Set NE1 to about 4. Set NE2 to about 5. Now Start your car. Adjust your NE1 until you get a smooth idle while the engine is still cold. Now start turning it down as low as possible while still maintaining a good idle. If the car starts sputtering and getting rough, you just went too low. Turn it back up very slowly until it smooths out. You want to leave NE1 on the lowest possible point with a good idle. Now set NE2 to be about 1 higher than NE1. This formula should eliminate any stalling or popping from the BOV being open. Theory: Throttle setting tells the SAFC whenever the pedal is depressed less than 1%, the SAFC should control fuel and ignore everything else (including the MAF) NE1 is the first RPM point you have selected in your NE Point settings. I put mine at 1000 rpm. I set NE2 at 3000, then NE3 at 4000, and so on in 1000 increments. Setting NE1 down at 1000 gives you the ability to control fuel at idle really well. Besides, you probably don't need to adjust anything between 1000 and 3000. (turbo spools after that, right?) Setting the air flow percentage at NE1 is basically telling the SAFC a number to use whenever it reaches that RPM and less than the throttle setting. So, as the throttle is let off, the SAFC looks at the NE1 and NE2 points. As RPM rolls back, there is going to be a reduction in air into the engine, yet the MAF has already seen it. The stock ECU is attempting to send the fuel for that air that is now missing... hence your stalling and backfiring. The SAFC catches that signal, ignores it, then tells the ECU exactly how much air flow you have according to your DEC AIR settings at those RPM points. Get it? RPM comes down, hits NE2, SAFC sees 10%. It tells the ECU it needs 5%. (because you picked that number.) Now the RPM won't dive so hard like it was. It reaches NE1, SAFC sees 6%, you told it 4% and it tells the computer only 4%. The idle sets steadily down to where its supposed to and everybody is happy. The SAFC is all about tricking the ECU into doing what you want it to.

The original write up and many other good write ups can be found on Zeroyon.com here:http://www.zeroyon.com/index/content/vi ... /LateDaryl

[WDRacing]

My car does exact same idle thing everyday...no problems there. Starts at 11/1 then eventually goes up to 14.9 which is where I set it to.

[huguetpj]

My car does exact same idle thing everyday...no problems there. Starts at 11/1 then eventually goes up to 14.9 which is where I set it to.

It's the water temp sensor, right near the thermostat.... or where it should be in my case. Not to confuse with the water temp gauge sensor. When the ECU sense a cold engine it adds more fuel. My car smokes like crazy when I start it in the morning.

[WDRacing]

Good thinking Pedro...

[huguetpj]

Good thinking Pedro...

Nah.... my car died one day and it would not start. It seems my temp sensor is crapping out on me... live and learn.