V-AFCII Questions/Problems

[Area51SI]

Okay, Im new to this site, and am hoping that someone out there will be able to help me. I purchased the APEXi V-AFCII controller awhile back and just got around to installing it yesterday, and of course there were problems. Everything started getting crazy when I tried to change the VTEC changeover RPM setting. Originally the V/T Cont read **** for L-H and the same for H-L. Once I tried to change it to 5800rpm L-H and 5000rpm for H-L, the reve limitor on the car was kicking it at 4000rpm and then the check engine light came on. The same happens no matter what i set the change over at. However, if I go back to default (****), everything is fine, with the exception of the check engine like that is now on. Will that go away or what? Additionally, when does VTEC kick in normally on the 03 SI? As it is now, the V-AFCII is showing that it is kicking in at 2000rpm....seems kinda low to me. Anyhow, any ideas/suggestions/comments or whatever would be helpful...thanks

[DynaSpeed]

First off - Welcome to EPhatch.

and that's right... VTEC x-over is at 2200. Changing this just doesn't seem like a good idea. If I were you, I'd keep the VTEC points at stock, and just use it for A/F tweaking.

[BlasTech]

Here is what you need to know.

1.) The i-vtec on the EP3 (02+ Si) activates a lobe-switch at 2200, opening extra valves once you get going. Below 2200, the valves close off to make the engine burn cleaner and more efficiently at idle or low-rpm cruising... this used to be called vtec-e (I like the term diet-vtec)

2.) i-vtec does continually advance/retard the engine and cam timing to optimize performance and efficiency.

3.) the 4000rpm cutoff is "limp mode". It's the engine protecting itself, because it senses something is wrong.

You can read more detailed descriptions of what I'm talking about here:

http://www.hondata.com/techk20general.html

[Area51SI]

Yeah I will be honest, half the reason why i bought this thing was to just have "another" gadet in the car that looks cool...hahaha...im such a loser, but hey, it does look cool. Im just hoping that as I add mods to the car, I will be able to utilize the V-AFCII a little more. However, any ideas on the check engine light? My friend said that is should turn off on its own, but i dont have a clue

[HONDAPOWERED141]

it will shut off on its own or you can unplug the battery, the si responds well to extra fuel just dont go to crazy, more than 8% is too rich and it slows down.

[AsH KatCH ME]

problem is you connected the VTM wire, which you arent suppose to do on ivtec cars..

[VIZHUNZ02SI]

well i have mines connected and if u go by the manual u wont have an engine light. if u try to wire it the rsx pin out youre goin to get a enigine light and you car wont rev past 4000 rpms

[JDM_EpTypeR]

to be honest the VAFC2 is a cool thing to look at but deadly if you do not know what you are doing i blew my motor because it was running to lean, my #2 Piston rings melted and cracked the wrist pin. you have one go somewhere that has a dyno and let them tune the car and teach you how to use it. as far as the change over, dont do it just leave it, i have a type-s head wit type-r cams so i can but even that requires a little know how because i had my change over at 5000rpms but my car still did not start pulling till 6000rpms (the stock change point) because the VAFC2 forces the cams to shift but the fuel and all the other settings are still at the stock point. so tuning is everything, get it tuned correctly and it will make all the differance.

[Nick497]

when u hook up the v-afc or the v-afc 2 do u gain horsepower? cause what i heard we dont have a vtec engagement point like the rsx type-s. i was thinkin about gettin one but if you cant change your vtec point and dont get horse im not gonna right now.

[HONDAPOWERED141]

stop worring about changing vtec the more air and the more fuel you put into the motor the more power you can make, what do you thing superchargers and turbos do , more air more fuel.so yes it does give you power

[Tenacious G]

you would have been better off with the SAFC. because essentially all you can do with the VAFC you can so with the SAFC.

gains will be minimal.

[LaxSi]

hey man i had the same problem i reset the configuration too 5500 h-l and 5000 L-h then i tried to find the code for the number eventually the maintence light came on and i disconnected it and rewired it. Next i went to Apexi.com to see the manual if it was right but i think in the japan site it tells you there is something wrong with one of the wires i think its the VTEC soloid something that on the ecu wire where you splice and clamp so check Apexi.com and download the Adobe program to interpret the japanese letters.

[HONDAPOWERED141]

if you guys looked in your manual there is an insert telling you the correction you need to make with your wireing, and the results are not minimal 10+ on a dyno is not minimal for 300 dollars.

[Tenacious G]

Originally posted by HONDAPOWERED141
if you guys looked in your manual there is an insert telling you the correction you need to make with your wireing, and the results are not minimal 10+ on a dyno is not minimal for 300 dollars.

sorry man, but i seriously doubt you'll see a 10 whp gain simply by tweaking A/F ratios unless you're running a boosted application.

[HONDAPOWERED141]

yes you can the dyno does not lie

[Tenacious G]

let's see some dynos