i just installed my apexi vafc...whenever i floor it...my car bogs and kicks back at 6500. is there a way where i can change that on the controller? i cant seem to find a way. i need it to let me rev up to redline at least.

would it be a wiring problem or just need to do it through the controller?

 

is vtec engaging?

 

yes

 

sounds like safe mode

 

Are you sure it is? It really sounds like it's:
#1. flooding itself, or possibly leaning out. I know you didn't hook up a VAFC without at least having a A/F meter.... that would be the worst mistake EVER.

#2. in safe mode. You're hitting your rev limiter for limp mode. Either that, or your car thinks that it's REALLY running without two cylinders.

You need to get an A/F meter BADLY. And have a pro check out the install and setup on the VAFC. If you've set it up on the wrong anything it could cause all of these problems.

 

Bad settings or bad install. It happens all the time. Get someone who knows what they're doing to look at it.

 

i think i know whats wrong...i think everything is ok...its just that my check engine light is on and i have to go get it reset....if the engine light is on...the rev limiter comes in earlier...correct? thats my problem.

 

http://www.hondaprelude.to/articles/mil_check.html

If your check engine light is on, then everything isn't "okay". Check what the MIL code is, then fix the problem.

Who did your install? One of the most common problems for intermitent MIL's providing everything else was installed correctly is failure to connect the VTM wire. The manual states it's not required on 5th gens, but it is.

 

pretty simple pal....hit the "back" button until you see settings...

then go to option #1...wide open throttle...

your running too rich or too lean... you won't even get a check engine light sometimes.
so start leaning it out, or riching it up from 3k-8k until youc an rev...

better yet...take it right to the dyno.

Jeff

 

it it hits hard at 6500 RPM, that means that VTEC isn't engaging, and you are hitting the first rev limiter. The wiring or configuration is faulty

 

If you haven't gotten it fixed here is the problem.

the problem is the VTM (blue) wire was not hooked up, the old instruction manual does not say how to hook it up but apex has a new one online. As far as hitting the rev limiter that is a safety feature that the car has when it is cold or sitting still. This shouldn't happen once it is hooked up right.

Also remember if you change the fuel settings too much it will trigger the map sensor in the ECU and cause the check engine light to come on. Also after you have the blue wire connected right go back and reset the whole ECU by touching the two battery wires together and then removing the clock radio amp to make sure.

It should all work fine then, just remember you will have to operate inside you ECU's range for air and fuel which is about 10-12% fuel changes, other than that it will be good to go.

 

jOJO IS CORRECT!


VNT

 

Ya, I already said that.

 

Also, for some reason you can't lean out the low throttle setting on the P13 ECU, you will throw a check engine light. I have a theory as to why but don't want to get into it right now

btw, don't **** with the VTEC engagement point unless you know what you are doing - a properly tuned VAFC has a crazy up-and-down fuel curve near the VTEC engagement point.


[Modified by JDM LUDE, 8:15 PM 12/17/2001]

 

I've installed a couple on OBDI Preludes and neither have had a problem leaning out low throttle settings. What code is it throwing?

 

MAP sensor. It throws the code when I am coasting in gear at idle. I was thinking its because the V-AFC modifies the MAP sensor signal to say that there is less air in the manifold then there actually is... at a high vaccum condition like that, I was thinking the sensor was reporting extreme vaccum (very little air) with the AFC telling the ECU there was even LESS air, therefore giving a value too extreme, to the point that the ECU disregards the sensor as faulty and throws the light.

This happens without fail, and only when the low throttle fuel curve is leaned out, and only when I am close the throttle.

 

so, what is the rite way of connecting the vtm wire to your vafc?
according to the book, it saids to cut the vtm wire, connect the vafc to the ecu part of the vtm wire and leave the othe part of the vtm wire alone.
is that the correct method?
i m also having some problems but i also have a safeguard v2 connected.
my problem is when i boost, i get no power at all.(use to w/out the safeguard+vafc install) but i have check and redone my wireing a thousand times. another problem is when i add +2 +3 +3 +2 +1 0 0 .... i have even less power at boost and when i check my plugs, it always says i m running lean. i check my egt when boosting and it reads 1400..
anyone want to help. thanks.

 

What u said about the VTM is correct, this is the exact same way mines is hooked up! On the Turbo Issue, I don't know! What type of map sensor u using? Missing Link?

vnt

 

DO NOT ENTER POSITIVE FUEL ENRICHMENT VALUES INTO THE V-AFC IF YOU ARE BOOSTING!

The V-AFC modifies the MAP sensor signal to enrich fuel. During boost with the MAP check valve your MAP sensor is reporting atmospheric pressure. If it reports anything higher, the ECU will freak out, which is the point of the check valve. To increase fuel the V-AFC will raise your MAP sensor signal which is already at atmospheric and the ECU will see positive pressure.

When the ECU sees positive pressure on the MAP sensor it assumes that there was an implosion in the intake plenum and cuts the injectors.

The Fields controller has a limiter and will not report positive pressure to the ECU, unfortunately the V-AFC/S-AFC do not have any limiter. The proper procedure is to run run the car slightly rich and tune it down with the V-AFC.

 

it happened to me before w/ my teg as well...

one of the wire that tapped to the ecu came loose so whenever my vtec engage..it acts funny like it was gonna die and kicks back. hth

Jeff-

 

well, i have no option except to richen up my fuel from idle to 5K. I dynoed it with a wideband o2 and its telling me i m running too lean. idle 15:1 - 13:1@5K. i have a non-adjustable fmu, so can't richen up fuel that way. if what u r telling me is true, why m i not getting any codes?

 

Take off your check valve and try to boost. Your car will buck and throw itself around as you transission from vacuum to boost. You wont get any codes.

 

got it.
still, it seems like the more safty features i put into this ride, the more it mess up. today, after a lone time, it started to jump at idle again. i unplug the vafc and it stop jumping. everything seems fine. i have everything solder on, so.. most likely it is not a loose wire. apexi will not help, claiming it could only be a loose wire connection with the vafc. i have check the freaking wire connections many times. does anyone here have the same setup? vafc with safeguard? please help. thanks.