Hay guys, im having trouble with my car where by it dose the whole inconstant idle thing (im shure you all know the one im talking about, because there's a new post about it every day lol) but it"s also thrown codes 3, 17 and 21. vtec control valve, speed sensor and MAP (im not sure in that order) and just recently its gone limp (im not sure if one of the codes made it go limp or a combination of the three). So i took of the ECU cover and checked out the wiring of my vafc (came withe car), now the wiring looks ok its got little plugs joining the vafc to the ecu, but the installer didn't just cut the ecu wire and join it to the vafc, it looks like he put new pins in the ecu plugs.
so that's just to give you some background info, my questions are:- are all the wires that come out of the ecu black.
Also once the vafc is wired in should there be any left over wiers coming out of the ecu, because i've got a black wire coming out of the ecu into the first loom pluge then out of the loom plug at the point thet all the rest of the vafc wires are spliced into, except this wire is just cut and taped up and conected to nothing. (so to recap thats an ecu wire going no where)
Sorry for the long post, i hope it makes sense and thank you for any help you can give. maby some people with vafc's can help. Oh and its a field vafc by the way. Also other mods are catless header back system. and i think thats it.

 

spacing helps with posts like that.....

the ecu wires are not black, you obviously have some sort of aftermarket harness.....

the speed sensor is not related to the vafc at all.....you really actually have an AFC, the vafc was a coined name by apexi....either way, unless the fields does something with the speed sensor, that is unrelated....

so you either have a bad ecu, or the wiring is faulty somewhere....

 

The only reasons I think they use the speed sensor is for the KPH speedometer it has on it and the option to set the dip switches to knock out the limiter.

Are you 100% sure you installed it right? Did you just tap the wires to those componets or did you run one half of it going to the ecu to the VAFC and one from the VAFC to the engine?

Where is you ground at? If you grounded it to your ECU move it somewhere esle.

Good luck and post your progress.

 

If you just tapped the wires it will make it run very very shitty. This guy I know put one in his CRX and did that and it bogged very badly. Then he would get CEL. I am guessing that it is very harmful to the engine too.

That is a fields diagram BTW. It might look a little confusing but it is really not that difficult to do.

here is a link to the page:

http://asia.vtec.net/beystock/....html

 

Thanks guys. i think i might have an aftermarket loom, because all the wires are black as mgags7 said, also because the vafc wires go strait into the ecu plug and don't have electrotaps.

I don't even know what im talking about, ill take some pictures and post them up soon and see if that helps.
Thanks for the replies so far.

 

That would be a big help. Post that up as soon as you can.

 

Aghhhhhh, sorry for the long wait, my brother lent me his digital camera but has forgotten to give me the necessary cables fore like 4 days straight. So sorry still no pics, but some updates instead.

Alright, so after farther inspection it turned out the vafc was attached by an aftermarket harness.
In-light of the problems i am having i decided to remove the unit, and in response the car has seemed to be running better (no cel light or anything), so im going to leave it out for about a month and see if any problems arise even without the unit, this way at least i can rule the vafc out of the equation.
The thing is all the problems had to be the vafc's fault because each problem corresponds to one of the units function's ie. vehicle speed sensor=speed display, vtec solenoid=vtec control function, map problem=full control function and so-forth.

The problem now is determining why the unit is f***ing up. Ive heard it mentioned that the crimp plugs should be cut off and the wires soldered together instead, would you guys recommend this also?

On another note the car preforms quite differently without the unit attached, the car just appears to drive more smoothly. also the transition into vtec seems more smooth, not the big kick it had with the unit on, but in-spite of this it seems faster all the way up to 7 grand.

Once again thanks for the help and sorry for the long post. Also please excuse any grammar, punctuation, spelling or sentence construction mistakes. (Its amazing how quickly basic English ability go's out the window at 12 o'clock and after a hard days work)