prox25

i jus recently droped in my new b18c on my 92 si evry thing turned out good car strted runin great but i have a problem i had an extra plug n i have a vacuum leak but because i didnt kno wut or wer the little hose was or wer it should be im completely lost on ther that plug *** frm under neath de manifold nd the vacume leak as well but im completely clue less on this!...any ideas are apreciated thnx in advance!...

this is de extra plug!... if it helps de plug has a yellow with a green stripe wire and a red with blk stripe!...

Former User

Does the MAP sensor have a plug? Is it a 3P connector? Post a picture of the pin side of the connector.

prox25

thats de plug!...+

and this is de vacuum leak i have under the manifold!...
thnx in advance

MHDesigns

Is it for IACV? I only ask because of its position in the bay.

prox25

Um idk man im a newbie 2 allthis!...i wouldnt kno wut does IACV mean?

MHDesigns

well in your second pic the plug is by the clutch and brake cylinders. Where does this plug come from. like where in the harness does it split from.

prox25

It splits frm undr de manifold, all 2gthr wit all de plugs frm under de manifold as well as lik on my 3rd pic wit de vacuum leak!...

94EG8

Extra plug is for the evap purge valve, which if its a JDM engine wont be there. Simply let the plug hang in the engine bay. The vaccum leak is probably from the IAB solenoid, although its really hard to see just where it is in the pic, a shot from a slight distance would help.

Former User

So you think the Yel/Grn wire is actually a Yel/Blk wire. That woulld then be a match with the EVAP valve connector.

94EG8

Thats my guess, actually I when I posted that I thought he'd said yellow/black, I guess sometimes you see what you want/expect to see. The three plugs of the type shown that should be in that general area are:

Evap purge solenoid -> yellow/black, red
Idle Air Control Valve -> yellow/black, blue/yellow
Intake air tempertature sensor -> green/white, red/yellow

Either way though, no round Q plug on the entire harness has a yellow/green wire going into it. As a matter of fact the only yellow/green wire I can think of in the entire engine harness is for the sending unit for the temp gauge.

Former User

For whatever it's worth, the Red wire of the EVAP valve changes to a Red/Blk wire at some point.

prox25

Thats de vacuum leak its a bit more under neath of de manifold but i jus pulled it out a bit for a better pic!...but i did notice its a very sloppy set up cuz its a pink wire with blue stripe n then it gets [iced onto a blue over by de battery tray n it *** frm de firewall!...

simpleEJ6

have you tried just plugging the vacuum leak up and seeing how the car runs?

prox25

no have not!...u mean lik jus putting sumtin 2 jus cover it up?...

Vindicator9000

Could be wrong, but I thought jdm B18C1s had an evap, but it's in a different location from the USDM ones.

OP - are you sure it doesn't plug into the white plug on passenger side of the intake manifold? I thought that was where evap was on those. EDIT: Never mind, according to diagrams, that's the IAT sensor.

As far as your vacuum leak... I don't have the diagram in front of me, but based on the location, it looks like it might supply the IAB canister, which is a little plastic box that hangs off the underside of the intake manifold. I see that you still have the IAB vacuum diaphragm, but is everything else intact and hooked up?

Vindicator9000

Here's a diagram of the IAB tank and related vacuum stuff.

What engine harness are you using? GSR? I'm really starting to think you're missing IAB parts. It looks like your vacuum leak might be the IAB solenoid, I guess... maybe. If it's a gsr harness but you're missing IAB stuff, you would have an extra 2-prong round plug under there where the solenoid should be.

Double check this diagram and make sure you have all of these parts and that they're all hooked up.

Simkin314

If you haven't already solved the extra plug problem...here are some pics that may help.

prox25

honestly man i have no clue exactly wut engine harness it is bcuz ther was a gsr on der previously but it blew n im jus using dat same harness, but another thing dat seems weird is dat it has alot of spiced wires lik all over!..jus recently i had vtec problems bcuz vtec n vtec pressure wire wer all cut up n very sloppy!...but thnx alot for that diagram!....

prox25

thnx alot bro!..but evry plug on de pics r correct i double chekt them n also had a friend whos a honda tech guy and they all seem correcti jus dont kno wer that 1 plug is for!...

Simkin314

On the B18C GSR, there is a vacuum canister beneath the snail shell manifold (controlling the intake butterfly valve, IAB). I'm leaning towards that (if you haven't already checked it). It is part #7 in Vindicator9000's diagram. The canister needs 2 wires to actuate and with a swap, it is necessary to run the wires.

If the canister isn't underneath the manifold, someone removed it and you GSR isn't utilizing the switched runner method.

Edit: Sorry, Vindicator9000 already came to that conclusion. I would probably agree with him

prox25

thnx alot man imma chek dat out right now!....

-__-

unrelated to the post, there are NO JDM B18C1's. lol.
sorry it bugged me.

Vindicator9000

yeah, #7 is the tank, #6 is the solenoid. Depending on what year your engine/ecu/solenoid are, there are multiple ways to wire it... dunno why, but they decided to change the wiring halfway through the gsr's model run.

So, depending on the year of everything, if that's an IAB plug, one side should run to one of 3 pins on the ECU, and the other side should run to a ground block. Or, one side should run to switched 12v, and the other side should run to ECU. Or, if it was added by someone later, who knows?

Honestly I wouldn't be surprised if someone removed it over the years. There's a somewhat misguided opinion that GSR IABs are not worth hooking up... When I was trying to figure mine out, tons of people on honda-tech told me to just pull off all that stuff and throw it away. In reality, they do wonders at smoothing out the vtec bump in the middle of the torque curve, and really do help drivability in the low rpms.

joelmatt89

could also be knock sensor, if it was something that was supposed to be plugged in wouldn't it throw a cel

prox25

OO SORRY 4GOT 2 MENTION BUT I am throwing a CEL and it is giving me knok sensor code!...