ProbeGT-ZE

here's what happens...just this morning i did a Bilstein engine flush, and an oil change w/ valvoline super syn 5w30 (i get this stuff for free, so yeah)...when leaving a light in 1st gear, the car feels like it's either running too rich (that's what the AFR shows) and it's slow as hell despite having boost showing on the stock meter(no boost gauge yet)...it's as if the engine was pulling back the timing because of knock...anyway...it'll do this for a little bit, then it'll suddeny go back to normal, then i have power again...i was reading earlier and i heard someone say that running a walbro 255 w/o a S-AFC is running WAY too rich..i HAVE an AFC, but the hi/lo settings are all set to zero still...my mods are as follows

Hacked MAF
Apex-i S-AFC
2.5" DP
Semi 3" Apex-i Dunk exhaust
Walbro 255 in tank pump
TurboXS Boost control (screw's backed out twice, roughly 2psi increase)
Shift kit
k&n intake filter
Hard up pipe
HKS SSQ BOV

help me guys!! i'm confused!! should i lean the mixture out more? what should i set the Decel-Air settings to?

ProbeGT-ZE

btw my HKS SSQV is vented to the atmosphere, could this be creating an overly rich mixture??

the decel settings right now are...
TH 3%
Ne1 8%
Ne2 9%

the Hi and Lo settings are all at zero (actually...on the Hi settings at 4000rpm it goes +1, then at 5000 +2 and so on till 7500rpm where it's at +4

MerF

My zeroed out S-AFC was creating an enormously rich situation as well. For some reason, zero is not zero, something still makes the ECU start to add too much damn fuel. I actually fouled out plugs in 1,000 because of the richness condition. Then there's the other possibility, boost leak. Your MAS is knowing the turbo is sucking the air in, but it's leaking out of your charge piping instead of going in the engine, where the AFC/ECU has already compensated for all the air it detected by adding fuel. Also experienced this...twice...lol.

execelon

so does this go away when it warms up ?
i won't even go there about venting the bov
of course it's gonna read rich your car has already counted the air that came in and you vented it. check your knock sensor if it's soft, sticky or anything like that replace it. the fuel pump will increase pressure. not sure how much but it shouldn't be that bad. and those air fuel gauges are almost worthless.

and no boost gauge?.....can i shoot you? .....please?

Hybrid AWD

you can run the walbro 255lph on stock injectors, ive heard a ton of people doing it... about leaning it out... yeah you could, but this i dont think would fix your stumble problem. Venting to the atmospher causes some problems with some dsm's (hopefully not mine) since the MAS is looking for that air to be return'd to the intake. I also know that the hacked MAS can cause some weird shit to happen, thats why some people put it back in when running the SAFC. Id wanna be in the car feeling it before i went and told you to do something.

projsr20det

I know with SR20s, the Walbro 255s usually add a pound or 2 of extra fuel. And with you running on a MAF system not being recirc., this will also cause a rich mixture.
Do you have a fuel gauge or an adjustable FPR?

ProbeGT-ZE

yea yea no boost gauge blah, i know...i'm pickin' one up on monday...anyway...i'll be checking for boost leaks, sticky knock sensor, and probably selling the S-AFC for a GM 3" w/ translator...but for now...i'm still stumped

ProbeGT-ZE

well i leaned out the mixture, and its starting to do better,....like -17 and stuff

TheSpeedFactor

if you are on stock injectors bro there is no reason for you to be around -17, did you do the blue wire mod on the AFC install? the BOV will cause a little bit of a richer mixture. i am keepin my AFC with the GM mas then going DSMlink V2. Walboro pumpin into stock injectors could have somethin to do. its not unheard of increasin the flow with more pressure behind the fuel.

MeanGreenGSX

you said you had the bilstien crap flush, did your car run like crap before you had the flush done? And you should know better than to vent to the atmospshere. -17 is defiantly not were your settings should be, niether is 0 though. -5 or somewhere in there is where it should be, just a guess, make sure your bov isnt leaking at all, and also where the bov return is make sure that is sealed all the way since you dont run that now