i recently installed the VAFC into my LS vtec. im using a 98 cx harness jumped to OBD1. i installed it to the jumper and all the wires are in the rite area (maybe not sure bout 4 wires. yellow, purple, white and pink, becuz i had to install a vtec wire becuz it was a non vtec harness). it powers on and everything and the sensor check works but but pressure doesnt say anything. everything else works but the engine wont start. im thinknig its one of the 4 vtec wire.




as u see in the diagram. the yellow and purple run to the ecu where the pressure and vtec signal is. and then it says the white runs to pressure input. and pink to vtec output. what confuses me is how its wired.

this is my current wiring. only the pink, purple, wite and yellow confuse me. can anyone tell me how it goes. concider that its obd2 nonvtec wiring harness jumped to obd1 with custom vtec wire

 

I don't see a white wire in your diagram. The white wire absolutely needs to be connected otherwise the ECU won't receive a MAP voltage and won't start.

The AFC gets wired in series with the signals it can alter (ECU's VTEC output and MAP input)..the one's wired in parallel are only for monitoring.

It goes:
MAP sensor -> white wire -> AFC -> yellow wire -> ECU
ECU -> purple wire -> AFC -> pink wire -> VTEC solenoid

 

the white wire is the turquoise that has an arrow with white next to it

 

The white wire doesn't go there. It's goes to the MAP sensor, not the VTEC solenoid.

 

okay .... do u got aim or yahoo? msn?

 

green and white or red and green wire?

 

Whatever color the middle wire on the MAP sensor connector is. grn/wht wire should be it.

I think the red/grn wire is for the reference voltage ground for the MAP sensor...not what you want at all.

 

thanks it works now, i sat around and thought bout how to wire it and it fianlly works. i ran the yellow to the map and the white to the map too and it worked.

 

So you have the White and Yellow wires physically tied together - as in, they are making electrical contact with one another? That ain't right...

 

The WHITE wire does go to the vtec pressure switch

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDM_JON &raquo;</TD></TR><TR><TD CLASS="quote">The WHITE wire does go to the vtec pressure switch</TD></TR></TABLE>

Huh?

Are you saying the Apex-i wiring instructions are wrong?

EDITED


Modified by EE_Chris at 8:49 PM 7/11/2005

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EE_Chris &raquo;</TD></TR><TR><TD CLASS="quote">

Huh?

Are you saying the GReddy wiring instructions are wrong?</TD></TR></TABLE>

greddy...i thought he was trying to install a VAFC from APEXI?? maybe i read wrong

 

the white and yellow wires are together...cut the pressure switch wire in half...the half that is still connected to the ECU you put the yellow wire....the other half the wire you cut you connect the white wire too which is the side of the harness

 

And where does the VTEC pressure switch come into play with what you're saying? Maybe I'm the one reading wrong but I thought the yellow and white wires had to do with the MAP sensor?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EE_Chris &raquo;</TD></TR><TR><TD CLASS="quote">And where does the VTEC pressure switch come into play with what you're saying? Maybe I'm the one reading wrong but I thought the yellow and white wires had to do with the MAP sensor?</TD></TR></TABLE>

no map has nothing to do with it...look at the wiring diagram...the yellow and white wires are labled(PRESSURE SIGNAL) yellow wire goes on the output ECU side...and the white wires input goes on the harness side..ive installed like 30 of these and with no problems and or mess with anything with the map sensor...just follow the wiring diagram..the 1st picture

 

How do you install a VAFC and NOT mess with the MAP sensor wire? That's the main reason you install it in the first place.

 

FR THE DARK PIE

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EE_Chris &raquo;</TD></TR><TR><TD CLASS="quote">How do you install a VAFC and NOT mess with the MAP sensor wire? That's the main reason you install it in the first place.</TD></TR></TABLE>
it works off the percentage of throttle from the TPS and RPM

 

MAP sensor = Manifold Absolute Pressure sensor

It's one of three key inputs to ECU's using speed-density to determine mass air flow into the engine.

AFC = air flow controller

I'll let you put two and two together.