Dave B

I downloaded Apexi's install for the S-AFC on the Maxima. It is extremely confusing. Do you remember how you wired up your S-AFC? The diagram for the S-AFC doesn't even come remotely close to the shop manual. Do you remember what pin #s you tapped into on the ECU? Thanks.

Dave

Keven97SE

I just looked at the manuals on the apexi-usa site and think that I used wiring diagram N6-a. I remember looking into the "Instruction Manual US Update" document, finding that the Maxima was supposed to use World N5-a, but looking at my harness connector and finding that N6-a matched better...there are only slight differences between those two connectors. I verified that those were the correct pins by looking into my FSM. I followed those diagrams solely and everything worked out fine.

See "Vehicle Specific Wiring Diagrams" at http://www.apexi-usa.com/pdf/afc_wire.pdf. On Page 3 (Page 4 accdg to Acrobat) there's a diagram of the color coding on the S-AFC wires. Match that up with the N6-a diagram on Page 19 (Page 20 accdg to Acrobat). The US Update document is at http://www.apexi-usa.com/pdf/afc_us_update.pdf.

Look over your ECU harness connector to make sure it matches N6-a prior to starting your work. If there are ANY discrepancies, look at some of the other diagrams for A32 3.0L Cefiros/Maximas. The World N5-a that may match your car. N6-a matched mine, but mine's a 97. Verify by matching with your FSM.

Make SURE to connect the two ground wires as per the diagram, with each wire tapped separately to the ECU ground wire, and the Brown wire closer to the ECU than the Black.

One more thing, I think that N6-a was what I used but I don't have my hard copy manual in front of me where I made notes and circled the correct diagram. Only going off what I remember here, and I think it was N6-a that I used.

Before you start the car for the first time, go to the "Etc." menu, set Sensor Type to HW-4 (Hot Wire Type 4), and Engine (Cylinder/Throttle Sensor) Type to 6 with a up/rightward-pointing arrow.

I set the Hi/Lo Throttle Settings to 39 and 40%. I used the ECU's diagnostic mode to find out that below ~35% throttle, the car went into closed-loop mode. If you make any fuel flow changes in that throttle range, the ECU will dial them back out to get back to stoichiometric. With Lo set to 39% and NO changes made at that setting, it ensures that all the changes you make in Hi at 40% throttle will not be dialed out by the ECU. The only time the AFC changes come into play is when you are at or above 40% throttle (well, technically, there's a linear ramp from 39-40%). For setting the proper fuel adjustments per rpm, well, there's really no way to do it by feel. Have to dyno tune it, which I have yet to do.

Dave B

Is there any possible way you could tell me which pin #s you tapped into for the S-AFC. It would help out a great deal. All I've got is a Chilton's manual and I doubt it is like the Nissan FSM. The Chilton's does give pin #s, wire colors, and what it's connected to. If I had the pin #s, I could easily install the S-AFC. What wire off the S-AFC goes to the throttle position sensor. They're directions aren't clear on how that taps in to the ECU.

BTW, I haven't bought the S-AFC yet. I just want to make sure it is a painless install.


Dave

Keven97SE

Have the FSM in front of me. Pin numbers are:
Power: Pin 67
Ground: Pin 55
Throttle: Pin 23
RPM Signal: Pin 5
Air Flow Signal: Pin 54

Diagram N6-a and N6-c both match my ECU connector.

For the throttle connection, look at the top diagram on Page 43 of the Instruction Manual. (The Vehicle Specific Wiring Diagrams document doesn't show you the throttle connection.)

That means that:
Power (S-AFC Red): Pin 67
Ground (S-AFC Brown and Black): Pin 55
Throttle (S-AFC Gray): Pin 23
RPM Signal (S-AFC Green): Pin 5
Air Flow Signal (S-AFC White and Yellow): Pin 54
Notes:
- Grounds MUST be connected as per the S-AFC diagrams, with each copnnected to the ECU ground 1 cm apart with the Brown lead connected closer to the ECU
- Note: White is input from MAF sensor to S-AFC and Yellow is output from S-AFC to ECU

Dave B

Thank you very much.

Dave

97blackv1

bump!
i have been thinking about getting one of these also

Keven97SE

I think we need to start a "Classic maxima.org" website for stuff like this.

Nismo87SE

I thought this post was old. Must've taking alot of effort to post this up given the search is down . The archiver gives you a .

meccanoble

iTrader: (22)

and it takes even more effort to resurrect this bisch

s0ber

iTrader: (7)

Sooo how much does those AFC's run for

s0ber

iTrader: (7)

lol ;-)

1235123123

BSwithTF

iTrader: (8)

Are these setting for an N/A car?

Nismo87SE

You might see better results by using an adjustable FPR. Either way you'd have to visit a dyno or use a wideband to get the target A/F ratio.

BSwithTF

iTrader: (8)

I am trying a V-AFCII with my '00 manifold. I want to use the VTEC out to switch the manifold. Only problem I'm running into is the thing reads in pressure since Hondas use MAP sensors. When he talks about setting the sensors to HW-4, the only thing I have for sensor setting is a screen that says "In" and "Out". Default is set at 6 on both of them. Is this the screen I need to set to 4 or is it totally different on the two models?

Sprint

iTrader: (10)

yeah those are for an NA car.

BSwithTF

iTrader: (8)

Anyone know about the sensor setting screen? Looks like this:

IN OUT
6 6

I can't find any direction as to what this page is for or what different numbers will do.

IceY2K1

iTrader: (3)

How does the "VTEC" signal work?

Is it just a simple ground at XXXXrpm or is it a frequency/pulse-width or what?

BSwithTF

iTrader: (8)

I called Titan Motorsports (where I bought it from*) and Brad told me to set both #'s to 4. He said the VAFC and the SAFC are wired the same except for the VTEC out and a wire for the knock sensor.

I haven't wired up the VTEC out yet. I read a while back that it's a 12V signal but I'm not positive about that yet. I'll let you guys know when I get it all working. Apexi's instructions leave a lot to be desired as far as explanations.

*-Titan Motorsports is great. I ordered the V-AFC and they sent me the V-AFCII for the same price and the express shipping was free.

IceY2K1

iTrader: (3)

Yeah, I know the eManage can change the VTEC point and also adjust AFR below/above it, so I'm thinking I can control my VIAS switchover with a relay or directly.

Let me know how it works out.

BSwithTF

iTrader: (8)

Got the VI working last night with the VTEC out controlling it. I tested the wire at changeover and it held a steady 14.8 volts until dropping below the set RPM. I can now control my rpms from my dash and can set seperate changeover points on acceleration and deceleration. Might be helpful if I figure out that thing's slapping shut for a split second if my shifts land just below the set rpm. I'm going to get it dynoed and tuned this morning at 10. Unfortunately, (I can hear you all cursing me) it's on a different dyno from my previous dyno's. I will however get to my old dyno place after the tuning is done and get a run in there so we can get a closer idea how much difference there is between MEVI vs. '00 VI.

I hear there's a difference between a Mustang dyno and a Dyno-Jet. Any one know what it is?