Need help with Apexi S-AFC.

[jinglebell17]

So I found the source of my car searching for the idle every once in a while. My Super AFC is not set right. And everything I set it to just makes it worse. Its the first generation model with the 5 knobs (one, 800.. two, 2400.. three, 4000.. four, 5000.. five, 7000..) i think that is what the knobs are labelled as. I am not familiar with this at all. My RX-7 had a 2nd generation model that was all digital and I understand how that one works but these knobs make no sense to me. Ive googled it a bit and basically all Ive deciphered is that the S-AFC is tapped into both the Throttle Position Sensor and Oxygen Sensor..

The only thing I can think of to maybe help someone help me out is that when I was swapping parts for my car to pass safety, I had to remove my screamer pipe and put a stock downpipe on from my friends RB20. Im lazy as hell so I didnt bother taking the oxygen sensor out of my screamer pipe and putting it in the stock one (instead I bought a Cherry Bomb O2 sensor plug.. its just a plug so it doesnt leak exhaust from the hole). Then during the time that I had the stock downpipe on (with no O2 sensor connected), I reset my ECU hoping that would solve my problem. It really didnt do anything.. I think it made it a TINY bit worse. Then when my car passed safety I put the screamer pipe back on and reconnected the O2 sensor.. I have not reset the ECU since the O2 sensor has been plugged in again.

Another thing, when my car is doing its funky idle searching, if I take it on the highway for about a minute and get back into the city, it will be idling normal (sometimes normal at 1,100 rpm and sometime like 1,500 rpm and a couple times sitting at 1,800 rpm for a bit haha)

I hope thats enough info. Maybe someone can help me figure this out.

[beacher1B0]

Your idle hunting could be related to your IACV or AAC valve or a Vacuum/Boost leak. Clean your valves and check for leaks.
I dont think your Safc would cause your idle to hunt. The important tap for your safc is the MAF signal, safc intercepts MAF signal and passes the manipulated signal to the ECU making it think there is more or less air passing by the MAF. If u remove your safc you have to reconnect your MAF signal wire to the ecu.
Google Safc Gen1 Installation Manual or Pm your email and Ill email it to you.
And, normal idle is 650 Rpm.

[jinglebell17]

I like when mine is around like 800-1000 rpm. I pmed you my email. Im new to RBs so I dont know where the IACV Or AACV is. The reason I thought it was my SAFC was because while its idling if I tweak the first two knobs even a bit, it will change but usually not for the better.

[beacher1B0]

SAFC - Turn knob clockwise = more fuel, turn it CC = less fuel. When i had mine hooked up I could watch my AFRs go up or down when i turned the knobs.

New to Rbs! You have some reading to do. Its a Nissan so its easy to diagnose and fix.
Find yourself R32 engine manual, R32 GTR Service manual and Nissan Fast. GTRPWR.c@m has them or just google to find. All 3 are to big to email thru hotmail.
The r32 engine manual will show you how to diagnose problems like your idle problem, sounds like TPS, IACV or vacuum/boost leak to me.
The r32 GTR service manual has lots of helpfull info that aplies Gtst's.
The Nissan Fast program is Nissans parts software, type in your VIN# and voila. Part #s with Diagrams.

[beacher1B0]

Check your email.

[jinglebell17]

i have original owners manuals. Its not like this is the biggest problem in the world cause when Im driving it does not do anything wrong. If I come to a stop and sit and idle for like 10-15 minutes maybe then it starts hunting for the idle for about 20 sec and THEN it starts dropping to like 200rpm and going up again to like 1200rpm. Then if i go drive it steady without stopping for about a minute then its fine again?!?! Its so weird. Like I said though its not a huge deal its just a little annoying.

[jinglebell17]

Check your email.

i went over the .PDF of the Apexi SAFC pretty much from top to bottom. All of my setting on the backside of the unit are set properly for the RB20DET. I was screwing around with the knobs this morning, letting it idle then taking it around the block, giving it up to about 4,500rpm once or twice. No matter what I tried putting the first and second knobs to (first always in a negative ratio and second sometimes in negative and sometimes in positive), SOMETIMES it will idle normally (depending on what the knobs are set at I had it sitting at 800rpm, also had it sitting at 1100rpm, and another time at 1400rpm. If I leave it sit and idle where ever its at, after about 10 minutes it starts to fluctuate about 100rpm at a time, and then gaining to about 300rpm. After about 10-15 seconds it starts fluctuating anywhere from 200rpm to 1200rpm and then it wants to keep on getting lower after that. Sometimes when I rev the throttle up to 3500 or 4500rpm and then catch it at 1000rpm as it drops back down to idle, it will stop and stay there for 10 seconds to a minute or so. then fluctuates again. BUT, if it starts fluctuating and I go drive it around the block and back home, it stops doing it and its back at square one (idling normally at 800 or 1100rpm for almost 10 minutes and then fluctuates again). When Im driving around in the city it almost never happens unless I hit like 4 red lights in a row it will start to fluctuate, but by the time I drive to the next one its idling normal again. Ive tried a number of things and after this morning Im under the impression that it is not as big as the SAFC. Because it makes no sense for it to idle perfectly fine and then start searching.

Another important point is no matter what, when I start my car with the engine cold it will idle perfectly fine until the engine temp gets to normal. And its about a 50/50 shot when the motors warm and I start it, that it will idle perfect or not.

[DreadedFist]

Clean your IACV. Do a vacuum leak test. Reset your ECU. I doubt the safc has anything to do with it. Seems like everyone deals with idle hunting sooner or later.

Start with the easy stuff first! When you take IACV off, just blast it with brake kleen and let it dry or use compressed air to dry it. When I did mine, the brake kleen went in clear and came out black.