Go48

iTrader: (7)

Posted this in the Super AFC section with no response, so I'm posting here for those S-AFC experts who don't frequent that section.
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S-AFCII installed on an S5 turbo.

Question is: Do I need to rerun setup after momentarily disconnecting the S-AFCII power wire from the ECU?

Background: I was at the track last weekend I was having a rough running condition at idle and a minor miss at high rpm. The problem was undoubtedly related to A/F ratio since the tailpipes eventually became very sooty black. So troubleshooting the obvious possible culprits like TPS settings, vacuum leaks, plugs revealed nothing out of spec. Then I checked out the S-AFCII harness connections at the ECU for any problems. [It was installed by a previous owner.] In checking the splices, the power wire (red) pulled out of the quick splicer. Fixed that and the other splices checked out OK.

So when restarting the car it would barely run. No rpm readout on the controller and check engine lights for TPS and AFM. As a stopgap I removed the S-AFCII from the loop and it runs OK now, but I want to get the S-AFCII up and running again. All help appreciated.

HOZZMANRX7

iTrader: (43)

The programming stays in resident memory even when you disconnect the power. So, something else electrical is going on. If the AFC's connections aren't soldered, then I'd bet you have nother issue at one of those connections considering it cleared up when you removed the AFC entirely. Remote chance the AFC itself has taken a dump, but I doubt it.

Does everything register on the AFC read out when the engine is running otherwise?

Go48

iTrader: (7)

The car would barely run after "checking" the splice connections and repairing the power wire splice. When I first started the car after messing with the power wire splice, the AFC display did not look anything like it did prior to my activity at the ECU harness. Which is why I suspected that the setting were gone. And, of course, in a panic I tried running setup and got completely confused. That's why I decided to remove the AFC connections and run without it, at least temporarily.

As you indicate, the manual states that settings remain in firmware when the car is shut down, so that was a bit of a surprise. Removing the AFC power wire should not be any different than shutting off the ignition, since the power wire is spliced into the main relay position of the ECU harness which has no power when the ignition is off.

Yeah, the connections are all quick-splice, and the ground wires are spliced together at a single point on the ECU ground wire (bad), so you may be correct about problem connections. If I keep the AFC I will redo all of the connections myself according to the installation manual. Or I may just run the car as is until I decide about going with a standalone. The car does have exhaust and intake mods, but the wastegate is ported, limiting the boost to about 7 psi.

arghx

iTrader: (3)

the grounds should be wired like this:



I think you should redo the whole installation. Check his AFM wire connections. You are supposed to cut the wire for the AFM. The SAFC is hooked in-line with the AFM, so one side of the cut wire goes to the SAFC input and one side of the cut wire goes to the SAFC output.

Go48

iTrader: (7)

Yeah, I have the S-AFCII wiring manual and noticed that particular instruction and the proper method of connecting the AFM. The AFM connection was as indicated in the manual, but the ground wires were definitely not correctly installed. As you suggest, a total reinstallation is probably in my future. I really hate working in that area, though, so I will wait 'til I have a strong motivation moment.

HOZZMANRX7

iTrader: (43)

Who did the original tuning of the AFC? If professionally done on a dyno, that has significant value all by itself.

Go48

iTrader: (7)

Dyno runs done by PF Supercars of MD. A noted rotary/tunner shop in the DC area. Not sure what you mean, though, about value. Do you mean since the power was removed from the AFC, that is gone as well. I would assume that but would be happy to find out otherwise.

ITSWILL

iTrader: (12)

if it is not reading the tach signal its not going to work properly, make sure you have a proper tach connection to the safc, If everything is good and it still doesn't read rpm I would say there is a problem with the safc. Also a wide band O2 and an afr gauge would be quite helpful to see what is going on.

HOZZMANRX7

iTrader: (43)

Meant that:

1. The market value of your AFC is much higher for another RX7 owner than an AFC not provessionally tuned.

2. Nothing gets the results out of an AFC like professional tuning. I put one in my S5 AutoVert. The first time I floored the pedal to passing gear, first impression was whooooooooowwwww!!!!!!!!!!!!!!!!

Scrims

iTrader: (2)

I'm not sure it will really be worth more. Each car is different, right? So his tune probably won't work as well on my car as it does on his, meaning I'd just have to have it tuned again, giving it no higher value in my eye. I guess if my car was EXACTLY like his in every way, then it would be of value to me, but otherwise.....

HOZZMANRX7

iTrader: (43)

If tuned for a Stock S5, would work perfectly in another stock S5 or modd's limited to reliability items. Not so much for a stock S4 or a what I would term radically modd'ed S5.