2G Problem with SAFC 2 Settings

[Spanky_DSM]

Im trying to balance out my air fuel ratio on the AEM Uego.

Ill Dump more fuel in on the safc and get the air fuel ratio to 14.5 at idle.

But after adjusting it, my wideband slowly creeps back up to where it was to begin with.

Any ideas? Am i suppose to go to initialize and click yes?

 

[4G Power]

Im trying to balance out my air fuel ratio on the AEM Uego.

Ill Dump more fuel in on the safc and get the air fuel ratio to 14.5 at idle.

But after adjusting it, my wideband slowly creeps back up to where it was to begin with.

Any ideas? Am i suppose to go to initialize and click yes?

You're not dumping fuel in with the SAFC, you're tricking the ECU into thinking there's less air, therefore putting less fuel in (leaning it out, to compensate for bigger injectors). The higher the correction number, the less fuel being dumped in.

 

[Spanky_DSM]

I knew i was gonna get a reply like yours.

I know how the safc works!

 

[clipto]

What size injectors are you using? I would ditch safc if your trying to make good safe power on your 18g. You can get the fuel right but who knows whats really going on with knock and what not. I would just run 450cc injectors and zero out the safc until get a better tuning solution. Safc is good cheap but you not going to get very far. All you can do is keep dialing it in until you get it right, but as previous post it only fools the ecu and going to never be 100% your always going to be fighting with the stock ecu settings.

 

[Spanky_DSM]

im not planning on making huge power.
The reason for the 18g is it came with a parts car and my t 25 blew.

I havent updated my profile but i just installed a vrsf intercooler.

and im currently on my stock 450's.

 

[clipto]

Then just zero out the safc you don't need any settings on the safc on stock injectors. You can try lean it out in the higher rpm range. Stock a/f at idle is the ecu pulling back and forth to get a 14.7 a/f ration, most the time it will be from 14.3-15.3 range. If something is wrong while the safc is zero out then there is probably another problem. What was your a/f ratio at that made you wanna mess with the safc, you just said you installed a fmic did you do boost leak test make sure nooooo leaks of air coming from anywhere? Just checking we always gatta ask.

 

[Spanky_DSM]

zero boost leaks, but have light crank case pressure which is being recirculated to the intake manifold and the breather port to the intake.

And the Reason for the safc is i plan on running evo 560cc injectors. I barley installed my safc today so i fiddled with it and saw online that the airfuel ration preffrence was high 14.s Mine currently bounces around 15.0 to 15.7 and thought id adjust that for now.

 

[clipto]

Is the crank case pressure happen under boost? I would try getting a new pcv valve. All good I just don't want you blowing up your car alot of us had safc phases, been there done that moment. The 15.0-.15.3 ok but being down towards the 15.7 is rather lean. Ever replace the fuel filter? For most part sounds like your doing good, just be carefull messing with the safc you don't want things to happen. Sometimes it will cause fuel trim malfuction check engine lights when the fuel gets messed with. I would disconnect the battery for a little and let it reset the ecu and zero out the safc and see if it goes back to normal, over all I wouldn't realy mess with it for now.

 

[Spanky_DSM]

well the pcv valve has a check valve in between but i should order a new one considering the one i have is not oem.

Thanks for the replies.

and you said 15.7 is lean, its hard to imagine im getting real bad gas mileage.

 

[clipto]

Well with dsm's I never really worry about a/f ratio at idle it's not ganna hurt anything as of what I have seen. But I was only worried about the 15.7 a/f ratio under different conditions of driving. How many miles do you get per tank of gas. I was get 300 miles per tank gas and that was on e85.

 

[Spanky_DSM]

i never fill up, usually around half a tank to almost empty i get around 120 miles.. I wouldnt mind the bad gas mileage if it had its power..

Car doesnt have much power and ive gotten codes for

rich and lean condition
and missfire. thats why i was trying to richen it up.. i was assuming it didnt have much power due to lack of fuel

codes pointed to o2 sensor and pcm.

i have both those parts for spare and swapping them there was no diffrence.. except for the misfire.. lose connection.

 

[dsmcurse]

aem ugeo's are known to give crappy ass readings. personally, id ditch the aem and get a PLX or Inovate. i personally had issues with it as well as 2 of my really good friends. we all hate the AEM ugeo junker. PLX i trust enough to watch my kid, not to mention my engine.

 

[Mischif]

I trust my aem uego with my life. Never had a problem with it.

Also you wont be able to adjust your idle air fuel ratio with the safc. The safc only works when your in open loop and the ecu ignores the o2 sensor. At idle your in closed loop.

 

[Spanky_DSM]

So i should disregard the low settings? And only mess with the high if i get bigger injectors to compensate for?

 

[clipto]

+1 never had problem with aem, I guess more people using innovate widebands now it's more of a personal preference. But exactly that at closed loop if you had bigger injectors you will still have to compensate(subtract) fuel for the extra fuel being dumped using bigger injectors with the safc but the ecu will always try to cycle and find a 14.7 a/f ratio.

 

[Mischif]

With a safc the best way to get the most out of it on turbo'd car is to hook up a map sensor and run that to the throttle input on the safc. But if your going to use the tps the best thing would be to set the low setting to 50%. I think thats what the stock ecu looks for before it goes into open loop. Adjust that for your low boost. Then set your high settings for about 75% and use the high settings to do your WOT tuning.

 

[Spanky_DSM]

ah alright, but just to make sure understand..

Low setting is Closed loop
and high is Open loop

And ive been reading mixed inputs for setting the high and low.
ive read to put the low at 20% and high at 80%

 

[clipto]

Those are throttle %'s. So if 80% is your high then when you floor it to 80% plus on the throttle the high settings will kick in anything under that will be your low settings. In between those %'s it will start rising to meet the high throttle %'s.

 

[sciondan]

I would get a data logger to use with the safc. If your idle afr is off, I would lean torwards a exhaust leak, o2 sensor, or wide band issues. I use a safc and have zero issues with it. Perfect afr and fuel trims all at 100%.

 

[PieEyedPiper]

...you wont be able to adjust your idle air fuel ratio with the safc. The safc only works when your in open loop and the ecu ignores the o2 sensor. At idle your in closed loop.

Ding! Ding! Ding!
I was getting really antsy that no one had mentioned that yet.

IMO, I probably wouldn't mess with it too much but leaning out at 5k+ a notch or two would probably be healthy. Similar to just changing all the 9.6 cells to 10.5 in ecuflash.

 

[Mischif]

ah alright, but just to make sure understand..

Low setting is Closed loop
and high is Open loop

And ive been reading mixed inputs for setting the high and low.
ive read to put the low at 20% and high at 80%

No thats not what i ment. Both low and high settings on the safc will only come into play in open loop. The low setting you can set for your low boost, meaning when you only boost anywhere from 1 to 5 pounds just driving around normally. Watch your wideband and your thorttle percentage to see what throttle point your computer lets the car go into open loop. Use that percentage as your low setting, with maybe an extra 5-10% added to it. Your high setting will be for max boost WOT. 80% throttle is good for that setting.