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Discussion Starter · #1 ·
Guys,

Need a little help with my wiring on my VPC and AFC. I made the mistake of soldering in my AFC on my fields harness before the VPC. I am having tuning problems and realized that my AFC does not do a thing. Last night I took out the yellow and white wires of the AFC and put them into my VPC wire ( yellow). My question is what do I do with the wire from the fields harness that is also yellow. Do I solder that in with my VPC and AFC wire or do I just solder it into my AFC wire and let the AFC wire connect to the VPC wire. I looked at MKIV.com but the instructions are a sentence long on how to hook up a VPC/AFC. Please help so I can get my car running properly.


Sincerely,
Staats
 

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The vpc has the yellow wire that generates the air flow signal. The safc has an input and output wire. Connect the yellow output of the vpc to the input of the safc. Then connect the output of the safc to the fields harness wire that was originally the maf wire.

So you are taking the vpc signal, running it through the safc, then it goes on to the ecu.
 

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Discussion Starter · #4 ·
One last question?

I double checked everything last night. Everything was set according to the instructions and I had everything right. The only thing I noticed was I cut the ground wire in half but I soldered a new wire in last night and did everything according to the instructions. My only question is on the VPC wire ( air out) I have the AFC white wire, yellow wire ( maf from the fields harness) and VPC yellow wire. Should I have the yellow MAF wire in there or should that be disconnected. My car at this point runs 11.0 at idle but then leans out when I put any load on the motor. I am lost and ready to ditch this set up and go AEM.


Staats
 

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All you have to do is connect the vpc yellow wire (air out) to safc white wire (air in). Then safc yellow wire (air out) to the fields harness wire (maf). Nothing else needs to be done to the maf wire on the fields harness. Make sure you either remove the maf sensor or unplug it.

If you think this is trouble and want to buy an aem, you haven't seen anything yet. It doesn't get any simpler than the vpc/safc unless maybe you got a gcc instead. It just plugs into the vpc.
 

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Staats,

Keep with it bud... Once you get these issues resolved you will thinks twice about going AEM. Just for the record, I thought there was something wrong with my VPC when it idled a little rich and I would step on the gas and A/F's would jump lean. This is normal w/ VPCs at idle (I have posted on it before) and don't let it fool you. Just take the car out for a spin, it should shoot for 14.7 once you get moving and go to 20.0 when decelerating.

Like supra400hptt was saying (and I believe the instructions as well), run the VPC output into the s-afc input, back to the ecu. I also put a resistor in my MAF to remove the CE light.

-Mike
 
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