ahobbs

Where is the "evap purge control solenoid valve". its on PIN A20 but i need to know where it is on the stock civic harness. I moved so many wires I dont even know where to being.

Ex. is it under the intank manifold?
its on a 93 civic

thanks

ahobbs

i think i found it just need to find both wire colors. I know one is red

94EG8

It's on the back of the IM. with 2 vacuum lines connected to it, one going to the IM the other the charcoal canister. Wire colors are red and yellow/black.

ahobbs

thank you very much. If you dont have the charcoal box its going to the intank. I remember cutting those wires lol.thats what i needed to know. can you take a pic of the wires if you have them?

ahobbs

man i found a red/yellow and yellow/black. it runs off the same harness with the knock sensor. i dont know where i put this thing the ecu shows a red with small silver spots, i cant seem to find it in the engine bay

Former User

The IAT sensor has a Red/Yel and Grn/Wht wire. What are the two wire colors in your IACV connector?

94EG8

Blue/black and yellow/black on a Civic harness.

I'll try to snap a pic for you later ahobbs.

ahobbs

yes i just went and checked, its a blue/black and yellow/black on my harness for the iacv.

IAT is Green/Black and red/yellow.

I have a set of red/rellow and a black/yellow coming from the same part of the harness as the IAT.

speedooo

it comes out of the same extension off the harness as the iat

ahobbs

cool that makes it easier to find. the small one right. thats what i get for cutting wires lol didnt think i would ever need them again

ahobbs

this is what i see the yellow/black and red/yellow are the loose ones
the black heat shrink is the IAT.
you can see up top the blue/black is the IACV

94EG8

That looks like it.

ahobbs

you know if there is a way I could be sure? I dont understand why the pin on the ecu is red/silver spots. I think the pin is A20

speedooo

The evap purge solenoid is screwed onto a tab on the top/back of the plenum near the 1st runner, iat is just below it, they're going to share a sleeve on the harness because they're so close.

speedooo

A20 solid red is correct

ahobbs

yeah now you see what im saying. Now yes I did find the the IAT and the wires that share the sleeve. just makes no sense why the color changed unless they change at the connector

94EG8

They usually do, take a look at the passenger's side shock tower plugs, a lot of the colors change from one side to the other. For example vtec solenoid is orange white on the ECU side and green yellow after the shock tower plug.

ahobbs

yeah i went and looked at that as well and noticed it. So could you confirm for me on your car or a stock car,

red/yellow and yellow/black?
then at the ecu red/silver spot? If so then ill feel good

94EG8

Here's where it gets weird. I've never seen one with a red/yellow wire. I'll take a look after, i've got a '93 Si hatch an a '94 DX sedan here right now, plus a bunch of thrashed harnesses. Wiring diagram just lists red all the way through (mitchell breaks up the wires at the plugs and shows you the different wire colors if the color changes)

speedooo

I'll do the same...i have a 94 cx at home in the garage and about 5 botched wiring harnesses in a box somewhere.

ahobbs

thanks for the help guys. I appriciate it. I re doing some wiring and i can use this plug for my boost set up. But i need to be sure its it first. I can always go directly to the ecu just trying to to do that.

Former User

If the Yel/Blk wire has battery voltage to body ground with the key in ON(II), and the Red/Yel wire terminal has continuity (but not continuity to body ground) with ECU pin A20, then you should be good to go, regardless of the wire color mismatch.

ahobbs

understood the first part, missed the last

Former User

If there is continuity between the Red/Yel wire terminal in the suspected Purge valve plug and A20 in the ECU plug, then the Red/Yel wire does run to A20, providing evidence that the suspected plug is indeed for the Purge valve, despite the wire color mismatch (Red/Yel wire rather than the expected Red wire).

ahobbs

gotcha,

hopefully someone else has the same wire lol. I just sold my other hatch so i cant look lol