Afc Help Needed

Speed_Racer

Member
:
2003 Mazdaspeed
Hey guys, I have a problem with my DSM AFC, the car floods at idle. It just stays rich with a steady stream of black smoke coming from the exhaust. The plugs drown at around 3000 rpm if I try to rev it lightly. As a last resort I tried to pull fuel at idle, if I type in any value lower than 10 the car runs for a while then shuts off.

I'm sure its installed right. I reset and reloaded the supermap many times. I have stock injectors. The car runs fine if I just reconnect the MAF signal to the ECU (bypassing the AFC). The vacuum source to the AFC is fine, I checked the highlighted cells during idle, they were all right, and all set to 10.

I'd like to know the values you guys are running in the output settings (only things I don't understand). My map B is set to all 0's, and Map A is set to all 10's in the idle related part of the speadsheet.

I'm out of ideas here, any help would be appreciated.
Thanks

edit: Output settings (don't know if any of this is even relevent)

PWM mode: pressure 0-30PSI/ 3vdc FS
OutputA mode: Aux fuel pump with abortive start time
OutputB mode: Over Pressure
OutputC mode: InjA and B over /latched

Over RPM: 6000
Fuel pump start pressure: -1psi
Overpressure: 1.1
Fuel pump run time: 3seconds
Over INJ%: 90
Fuel pump start time: 120seconds
 
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He's trying to use the super map. The car runs like total ass, the a/fs were in the 9.6-10s at idle.
 
get a unichip dude i have the dsm afc its no comparison to the unichip. I have nothing but problems with dsm afc. Im getting unichip.
 
Don't like the unichip, I'd like to tune my own car.

Yes, engine settings are 4cylinder 4stroke. The only settings I can't understand are out put settings, which I have come to believe is causing the problem (asside from the unit just malfunctioning), I think the afc is puttin out too much voltage to the ECU. Don't know if the car thinks its in boost or what.
 
uni-chips are very limited. While the PnP concept is great it doesnt work well once you plan on boosting more.
 
I'm trying to remember what my map B settings were. I have a feeling it was 10 for all values, but I could be wrong. I'll check it out if I have time tonight and if it ever stops raining.

My supermap settings in vac are all set at 10 and I have no problems with stalling or flooding. There was a thread on the AFC about some psi setting for the map that sometimes gets messed up sometimes and needs to be set correctly in order to have the thing work correctly. I'll check my output settings tonight if I have time as well. I need to start toting my laptop around so I can just work on my car at any given time.
 
also, when I look at the real time gauges, a cell value of 10 = 2.5V . . . I was under the impression that a cell value of 10 = 0V.

I typed in all 0's for MAP A & B and the car idled better, still rich, but it could rev. In the real time gauges a cell value of 0 = 0V.

Now I'm more confused than ever. I'm not sure if its in signal modify mode or what.
 
I also did the built in real time test thing. With PWM mode of 0V the car idled better, with a PWM of 2.5V, it started to flood again, a PWM of 5V the car shut off immediately.
 
id jump on the airflow site download any map and try it again.
i say that cause it copies the settings and what you have inputed may be incorrect.
pm sent
 
This is PSI thing but i dont think he saw a problem with that.

peepsalot said:
Somewhere in the settings(don't have it in front of me) there is a setting called "Over Pressure", this should be set to around 1psi. Apparently there is a glitch that can cause the map to reset this value to -18psi or something, which causes the AFC to override the O2 sensor even at idle(put it into open loop). John at airflow logistics told me he thinks this value is changed somehow when transferring the file from win2k to win xp or something.
So first thing I would do is check that one.
Also, make sure you have a proper vacuum/boost source getting to the AFC and verify these values in the software.
 
I've downloaded the supermap twice, reset the AFC, and then uploaded the supermap. I've re-uploaded the supermap at least 10times in 2weeks.

Hell, the car revs better at idle with MAF unplugged and the AFC hooked up. The MAF isn't even 6 months old, and like i said the car runs fine when everything is put back to factory, fuel cut and all.
 
Only other thing i can think of is the IAT Sensor, when can pick up some carb springs and do a litte number on the EGR and clean up the o2 sensors...
 
Ya that is what happens with teh DSM AFC. I had it for a while but got rid of it. What basically was happening from waht i saw was that at a value of 10, the car was acutally not getting the input signal on the output line. This happens on a lot of cars that i've seen. My problem was that the AFC would run more lean causing the car to almost stall while at idling. Others i've seen would make the car run really rich. so u must have the really rich ones. I've talk to John about controlling the idle but since i got rid of mine, i didn't follow up on it.
 
just great, thats exactly what I was afaid off, sorry dude, but I hope your wrong. Even tho I was hovering around that same conclusion.

Well at least some of them work.
 
Do you have the vacuum/boost line hooked up properly? There is a way to see the pressure readings from the AFC while the car is running. Are these readings normal?
Only other thing I can think is to re-check your wiring. Did you use crimp on connectors? They don't always get a good connection. Double check those. Best bet is to solder the wires though. Got a pic of your wiring?

I don't know if all the settings you listed are normal off the top of my head, but I believe there was a sheet of paper that came with it that had what the specific settings should be for the MSP version.
 
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noclue119 said:
Ya that is what happens with teh DSM AFC. I had it for a while but got rid of it. What basically was happening from waht i saw was that at a value of 10, the car was acutally not getting the input signal on the output line. This happens on a lot of cars that i've seen. My problem was that the AFC would run more lean causing the car to almost stall while at idling. Others i've seen would make the car run really rich. so u must have the really rich ones. I've talk to John about controlling the idle but since i got rid of mine, i didn't follow up on it.

Wow, I am in the process of hopefully getting one of these and this is the first time i read something negative about the DSM AFC. Do a lot of people have problems like this?
 

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