I did a search and only came up with one old topic with all broken pics, and not much info on the IACV wiring.

Basically a co-worker of mine has a Z6 head on a D15B7 block, and the only intake manifold he has is the D16Y8 manifold without air injection, which is a good thing.

The D16Z6 intake manifold has a two wire IACV, and obviously the engine harness has a two wire plug for the IACV as well.

The D16Y8 IM has a 3 wire IACV - I know it's possible to convert the Y8 to 2 wires or something like this because I've seen a "how-to" on H-T before but I can't remember when.

If anyone has any first-hand experience with this, or a link to a thorough how-to that would be awesome, because my co-worker is looking to finish the car this weekend.

Thanks in advance.

 

What car is this going into?
If its a obd1, swap the EACV with a 92-95 2 wire type

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by z6_EF_obd1 &raquo;</TD></TR><TR><TD CLASS="quote">What car is this going into?
If its a obd1, swap the EACV with a 92-95 2 wire type</TD></TR></TABLE>

Unfortunately it's no as simple as just switching the IACVs because the 3-wire type is located at the bottom of the throttle body, so it's impossible to just swap the IACV out because the 2-wire mounts in a completely different location that has no bolt holes for it.

It's going into an OBD1 car, but that's kind of besides the point now because I've found out now that the only way to get the IM to work right is to drill/tap the bolt holes to mount the 2 wire IACV and mount it on the back of the plenum where it would be on a Z6-type manifold.

Oh well. I guess drilling/tapping this manifold is easier than finding a 5-speed manifold.

 

I think I might have what you were looking for, the 2 wire vs 3 wire IACV...

saved it a while back:

 

Dude that's an awesome reply with the chart and all, and I appreciate that. I do think though that it won't apply to me because we're using an OBD1 P28 ECU, which from my understanding won't even be possible to run the 3 wire IACV anyways.

It might be possible, but I'd need the pin locations as it relates to a P28 ECU.

Thanks for the reply though - that will certainly help for OBD2 swap stuff.

 

are you using a automatic d16y8 intake manifold from a 96-98 and keeping the AT throttle body on it?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Bense &raquo;</TD></TR><TR><TD CLASS="quote">are you using a automatic d16y8 intake manifold from a 96-98 and keeping the AT throttle body on it? </TD></TR></TABLE>

No he wants to run the D15B7 TB.

...and he's already ported the holes for the OBD1 type IACV, so we're good there.

 

I'm confused. you have a obd1 car with a 2wire IACV plug and you have a 3wire IACV that you want to use?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Bense &raquo;</TD></TR><TR><TD CLASS="quote">I'm confused. you have a obd1 car with a 2wire IACV plug and you have a 3wire IACV that you want to use?</TD></TR></TABLE>

Originally yes, but now that he's drilled the ports and tapped the hole to mount the 2 wire OBD1 IACV on the Y8 manifold there's no need for any wiring issues.

 

so basically you have a d16y8 intake manifold that was for an AT, but you drilled and threaded the holes on the rearside of the intake manifold so that the IACV with the bolts closer together can bolt up to it.

and you have two IACV's, one with the bolts furhter apart. that won't fit on the y8 intake manifold, but has 2 wires.

and then you have another IACV from the y8. the bolts are closer together than the b7 one, and it fits the IM, but it's 3 wires, and your harness is 2 wires.

wouldn't you just get a 3wire plug and do the reverse of step 2 in the picture above?

 

He's basically fitting the OBD1 D15B7 IACV onto the Y8 manifold so there's no wiring changes needed whatsoever.

It looks exactly like stock where the holes are drilled/augered out - I mean it really looks stock.

 

Then why would he need to convert anything? Seems like he retrofitted the d15b7 IACV to the y8 intake manifold.

I'm still not sure what you're asking here.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Bense &raquo;</TD></TR><TR><TD CLASS="quote">Then why would he need to convert anything? Seems like he retrofitted the d15b7 IACV to the y8 intake manifold.

I'm still not sure what you're asking here.</TD></TR></TABLE>

Okay AT FIRST I was aksing how to retain the 3 wire IACV, but after I realized there's no way to keep a 3 wire IACV on an OBD1 P28-equipped car we (my co-worker and I) decided the easiest way to remedy this whole situation was to just drill the damn manifold and bolt the OBD1 IACV 2 wire to the Y8 manifold.

Basically there's no wiring question at all any more - we just didn't want to have to drill the **** to begin with, but it's donw now, so oh wells.

 

glad I could help