Will an SAFC cure this?

[RocketDSM]

Here is the trend I have seen in my car: Idle up to -10 inHg it runs lean. -10 inHg to 6psi it runs stoich. Above 6psi it runs dead rich. It would seem to me that my car is telling me to get a SAFC and even this crap out. Am I off base? Is that all I need or am I missing something in the grander scheme. I have a 255 pump sitting on my floor because I'm afraid to install it and run dead rich ALL the time.

 

[candela]

Whenyou told us these conditions, is this a wot from a dead idle.... I doubt it. If your using some an autometer a/f gauge or something similar you really cant get much from them. For normal cruising and idling and very light throttle your enigine will try and run stoich., meaning it will vary from lean to rich, lean to rich and back and forth just searching which is quite normal. Anyhow, if you are using a light like the autometer, rich can be anything from like .75 volts to 1.0 volts, so its hard to say if you are running rich anyhow. It shuld stay in the green any time you put your foot to the floor. if you dont have one and are referencing from some type of o2 voltage than post it up and we can further diagnose. But I dooubt that the car is running lean or rich, its probably just right. It should account for ore fuel as boost rises which is just how the FPR works in coherence with the ecu, its normal. Id throw the walbro inanyway, and if your worried about richness get a fpr. An afc can help thinngs but it really doesnt ever cure anything. It never cured my fuel cut even after injectors...

 

[RocketDSM]

I am talking about my everyday driving. Normally, I don't cross 6psi unless I'm at WOT, but it's right on the nose EVERY time no matter what I'm doing. As for the guage, yes it's an autometer and I know it's not all that accurate, but the trend is what bothers me most. I know it's running rich (just like the gauge says) because when I back off I get a backfire (sometimes between shifts too). I have a B&M CommandFlo (I know it sux too), running just over 50psi right now. If lower it, the car stalls at idle. If it's not pegged to one extreme it does to the bouncing thing. I understand that's normal. My problem is more the two extremes. Especially the rich side. The lean side is in vacuum so I'm not worried about detonation or anything like it. I want my crisp response and mileage back to where they belong. Seems like most people still get 20+mpg, I'm futzing along at 10-12mpg. Hope this helps some. But the question still remains...will the SAFC fix it? I've also been thinking of a DSMLink or other standalone, which I know would cure it. Problem is that I have to drive the car everyday. I can't take it down for more than three days, and even that is pushing it.

 

[candela]

Well I read all your posts. You dont really have any hugely significant mods done. Y0ou do however have lots more air going and flowing over stock... is that why you turned up your fuel pressure? You are worried about fixing a little bit lean condition when your not even at full throttle? That really isnt to big a deal as Im sure its not really lean as you think it is. If all you want is to solve this problem I wouldnt get an afc because it wont cure it. The afc doesnt tune fuel for load or throttle position it tunes for to points only either WOT or low throttlw w/e you set them at, and it makes some hazy little adjustments in betwween your two settings. Its decent for someone without a lot of tuning ability but it doesnt really solve many problems like this. You should try turninig down your fuel pressure, you are doubtfully running the 450's over llikr 80% duty with only 15psi and a stock turbo. Try that, maybe get a new o2 sensor or at leist test yours and go from there. BTW- there arent too many heavy modded dsm's here that get 20+ anymore. I usually get aroung 160-200 MPG depending how I drive....

 

[RocketDSM]

Huh? Whose mod list did you look at? I'm on a 16G (agreed not huge, but not stock). I'm not worried about the lean side (as I've stated in every post). I want to eliminate the fuel dumping routine occuring everytime I try to accelerate. As I said in the post right before, I can't lower the fuel pressure or it stalls out at idle. It also won't accelerate worth noticing until 2500rpm when I turn it down. When I had my old Apex'i SAVC-R it was registering DC's above 80% all the time. When it was stolen, I lost the capability to watch it anymore. I have two brand new O2 sensors, so that's not it. I figured the SAFC wouldn't help, thanks for confirming that part. I remember plugging the numbers into a system that would calculate required injector size for a certain horsepower based on a bunch of other things (about a dozen variables). It confirmed that a 4G63 with even a mildly out of spec fuel system would overrun the 450's in a heartbeat. How accurate that system was, I don't know. I'm thinking that I might go to a larger injector when I get the money. Bring the pressure back down and see how that works. Maybe the stock ECU is saturating my injectors. Anyway, thanks for the help. Kept me from wasting a bunch of money.