Help with harness plugs and one vac line at the bottom of the intake

[gaboonviper85]

What do these 4 plugs go?

do I have these grounds bolted up properly? They are bolted to one of the two tabs at the bottom of the intake

and this vac line that is pretty big and points towards the block...I know it's hard to see but it's red...I know two of them are the fuel pressure lines but the 3rd larger one that is facing the block between the two intake runners I can't seem to find it's home.

 

[Poodles]

Vac line goes up to a piece of hard line that bolts where the ground for the coilpacks goes that leads over to the BOV (very indirect path it runs)

 

[nick88]

The wires- the one with the square plug and the red loom looks to be abs going to trans, and the other square one with blue loom looks like reverse lights.

The rounds plugs go into the body harness I "think".

 

[radiod]

Plugs under the intake are for VSV's, knock sensors, starter, ECU ground, and AC if I remember correctly.

The two big round ones are the knock sensors

VSV's are smaller, 2 wire plugs.

Starter is a brown clip single wire.

ECU ground is the one with an "O" crimped end (I put mind on an intake mani bolt)

AC I can't help with much because mine's gone and has been out of the car since before I owned it.

I do remember there was a another 2 wire plug that I couldn't figure out where it went. I checked on my buddy's bone stock MKIII and saw his was unplugged too, so I left it as is. Haven't had any problems or anything, but I wouldn't mind finding out what it's for myself sometime...

As for VAC lines, a picture speaks better than words . You can click on it to blow it up to huge size. Article includes hose lengths etc.

http://www.cygnusx1.net/Supra/TechTips/vacuum_hose.aspx

 

[Poodles]

That image doesn't show the BOV line

 

[nick88]

That image doesn't show the BOV line

It shows where it doesn't go.

Plugs under the intake are for VSV's, knock sensors, starter, ECU ground, and AC if I remember correctly.

The two big round ones are the knock sensors

VSV's are smaller, 2 wire plugs.

Starter is a brown clip single wire.

ECU ground is the one with an "O" crimped end (I put mind on an intake mani bolt)

AC I can't help with much because mine's gone and has been out of the car since before I owned it.

I do remember there was a another 2 wire plug that I couldn't figure out where it went. I checked on my buddy's bone stock MKIII and saw his was unplugged too, so I left it as is. Haven't had any problems or anything, but I wouldn't mind finding out what it's for myself sometime...

As for VAC lines, a picture speaks better than words . You can click on it to blow it up to huge size. Article includes hose lengths etc.

http://www.cygnusx1.net/Supra/TechTips/vacuum_hose.aspx

those round plugs are not knock sensors.

 

[radiod]

The wires- the one with the square plug and the red loom looks to be abs going to trans, and the other square one with blue loom looks like reverse lights.

The rounds plugs go into the body harness I "think".

...and that would be why neither of us have reverse lights. :icon_lol:

As for the vaccuum lines, I started writing it all out and then read over it again and realized I couldn't even understand it. So I said screw it, put the pic in instead. Thought it was the same one that I used when redoing my lines, but I think I recall getting an "edited" version with a bit of a clearer view of where some lines went and whatnot.

 

[nick88]

...and that would be why neither of us have reverse lights. :icon_lol:

:yelrotflm Probably wasn't plugged back in after bhg job.

 

[gaboonviper85]

Ac plugs are up front....I have the knock sensors plugged in as well as the two vsv's...and the two grounds....those big round plugs don't reach far enough to go up front...I can't figure this out!

The harness is from an auto and my car is a 5spd...if that helps.

Poodles gave me the answer on the vac line as he knew exactly what it was....so please people don't just throw ideas and whatever as it's very confusing....I know yall are trying to help and I appreciate that but don't help me if you don't know the answer.

Thanks poo!

 

[gaboonviper85]

Vac line goes up to a piece of hard line that bolts where the ground for the coilpacks goes that leads over to the BOV (very indirect path it runs)

Suppose I can cap that off and T into a different line for an aftermarket bov?...

 

[nick88]

Suppose I can cap that off and T into a different line for an aftermarket bov?...

No, just take the line off of the stock bov and run a longer line to the aftermarket bov.

Ac plugs are up front....I have the knock sensors plugged in as well as the two vsv's...and the two grounds....those big round plugs don't reach far enough to go up front...I can't figure this out!

The harness is from an auto and my car is a 5spd...if that helps.

Poodles gave me the answer on the vac line as he knew exactly what it was....so please people don't just throw ideas and whatever as it's very confusing....I know yall are trying to help and I appreciate that but don't help me if you don't know the answer.

Thanks poo!

The plugs are for the auto trans, you will need to bypass the nuetral safety start switch on them.

http://www.supramania.com/forums/showthread.php?t=46586&highlight=bypass+nuetral+safety+switch

 

[gaboonviper85]

I appreciate your help...but I don't have a supraforums account:-(

 

[nick88]

I appreciate your help...but I don't have a supraforums account:-(

Heres the whole thread

Since it seems like I'm the only one that's done it, don't get me wrong - others have, I know - just NO ONE during my search was able to provide exact details.

Ok, well... here goes nothin'.... my attempt at enabling the reverse lights in a "how to" thread.

I don't have a schematic book, so connections will be based from plugs and wire colors in my '87. And for ease of install... I cut the harness from the auto tranny (basically wanted to use the plugs).

In the attached pic, from left to right, you have the following:

1. 3 wire round plug, wht/blk spliced together enable the bypassing of the clutch (ie. pedal pushed in isn't required to start the car) and the blue is 1 of 2 wires needed for the reverse lights

2. 6 wire round plug, this plug actually tells the ECU which gear the car is in. If you searched for "auto cookie" you'll find some more info on what lead to the connections. Anyways, the only wire needed from this plug is the blk one (this is 2 of 2 for reverse wiring)

3. 6 wire square plug. not used for 5 spd. IIRC, it was linked to the 3 solenoids on the DS of the Auto tranny

4. 4 wire square plug, its a direct plug'n'play for car's with an ABS system.

Now... just connect the Blue wire from item #1 above and and the blk wire from item #2 to the reverse sensor plug found on the PS side of the 5spd. tranny and your done. Working reverse light!

good info def getting saved. Do you have any info on wiring the cruise control cut switch?

I do (sort-of), but since I haven't verified its operation yet... I'm holding the info. Maybe once the car is back on the road... I'll do a write up on its wiring as well if it works.

HTH (the above mentioned info),
Patrick

Nice write-up and pictures -- I'm putting a link to this thread in the FAQ sticky. I would be using this info, but I will be cheating by using the 5spd harness and ECU

Cool... glad to help the community.

I opted for keeping the Auto harness mainly because of $$$. Its workable with trial and error. lolz

However, unless your changing the in-car harness as well... your curise won't work either (neither will your clutch safety for that matter). That wiring isn't in place for a Auto'd Supra.

The cruise needs the clutch sensor (on the peddal) to know when to stay activated... the clutch also needs the 2nd sensor if your not planning on by-passing it to start.

Thanks Pmpaluda its good to know where the hanging wires go
will do mine tomorrow.
Hopefuly one day you'll figure out how to make the cruse work

Dang that was my # 100, good thing it was a Thank you post

Yeah, thanks. I have a 5spd donor car, and my car is completely gutted so it shouldn't be a problem to remove any interior wiring harness either. I'll be sure to report which ones I've used. I do not have cruise, but I've seen too many idiots turn the ignition on (standing outside the car) with the car in gear -- so I do want the clutch start safety feature. I do plan on wiring an overide button though -- in the event the car breaks down I could use the starter to drive the car off the road (or up the trailer)

My reverse if finally done... wired I should day. Basically, I saved ALL the wiring form the auto that was salvagable before throwing it in the dumpster.

The following is the short harness I threw together... it retains the 2 large round plugs. Enabling the reverse lights is essentually a "Y" configuration to the 2-wire plug (on left).

well thats exactly one of the things I needed to know. Thank you

What kind of costs could I be looking at if I do the 5-speed swap, versus upping the auto tranny? Keep in mind, I'd be adding a clutch and most likely a pressure plate, and flywheel, or whatever else I should drop in to handle 350rwhp. Sorry for my not knowing, I've been studying the auto way too long, don't know much about upgrading the R154.

tranny - who know's??? $100-400 depending on condition and/or "who ya' know"

NEW clutch/flywheel kit - $800+ (ex. my SPEC stg3/Al flywheel) plus $100 or so for the hardware between the flywheel and the base trann shaft)

Various parts (driveshaft, brackets, lines, pedals, etc...) - $200+

I've purchased most of the "various parts" needed mainly from a few people... what parts I could afford, what parts they had, etc... you may find it better to find a complete parts car.

Obviously my car was an auto before... I guess that my answer as to what it takes to build a auto.

HTH,
Patrick

So, basically, it comes out to being about the same price wise. I've got some thinking to do then, on whether I want to upgrade the auto or go 5-speed, and upgrade that. I really am liking that auto though.

Doesn't an auto tranny have lower gas mileage than a manual car?

do you have any pictures of the actual swap?

you know droping the tranny.. hooking up the clutch peddle, mounting the clutch master cylinder.. ect...

just picked up an 88 auto.. and tring to source information before i begine. building with your eyes closed cost alot! of money :bigthumb:

Did you figure out which plug on the main harness is the one that goes to the clutch switch? I am putting a manual harness and ECU into my old Auto car (thats converted). I dont want to have to change out the dash harness though.

Jeff G

hey im doing the same swap but im findin my wires are different colors?? the tranny has 2 black wires. and my wire harnes isnt the same its from an auto can any one help me out

just got done with my auto to manual swap the other day and I hooked the wiring up just like you said except that I hooked my park/neutral switch up to the clutch safety switch and walla I got cruise controll and reverse lights and car don't start unless the clutch is pushed all the way in. doing the change over isn't teribly hard to do. about as hard as changing a clutch. and anyone that needs some help with their swap shoot me a pm and I'll help as much as I can.

P.S. lots of mechanical advise on how to get at certain bolts from ma71supraturbo

were does does #1,2 wires connect to the manual transmission like which part do they come from????

Does anyone know the best way to stop the O/D Off light from flashing? I was thinking just disconnected the ECT computer, remove the lightbulb as a last resort.

just need a little clarification, when these wires get connected to the reverse sensor plug, is it black to black and blue to white? or does it not matter?

I heard from a guy on a forum saying that keeping the stock automatic ECU when doing a 5 speed swap. would cause the boost to spool up slower in between shifts since the auto ecu is set up different than the 5 speed ecu. Is this true?

No, not true at all.

Also, to get cruise control working:

Go to the cruise control box (located above the clutch pedal) and cut the black/white stripe wire. Wire each half to a terminal on the switch at the top of the clutch pedal. Voila, you now have cruise control that cuts out when you press the clutch pedal.

thanks for the info planning to do the 5 speed swap was nervous about the park/netural safty switch

I would like to just wire in the clutch/neutral start to the auto dash harness as well... Just hadn't got to it yet.

Halp, pics aren't showing anymore! I'm almost done with my swap, except for this part!


Edit add: If anyone has the pics (or has done the splice), could you tell me which one of the six pins you hook up to the reverse light? I don't have a black wire on it!

Ok, looked through the TEWD, and it's the middle wire of the bottom row of the 6 pin circle plug.

 

[nick88]

^notice in the first pic those are the plugs you asked about.

 

[gaboonviper85]

No pics are showing up:-(

 

[Poodles]

Yeah, I just extended the line on mine as well, the stock BOV vacuum source is pretty strong.

 

[gaboonviper85]

I really appreciate the help...I'm sure the info you just posted will help...pics would be awesome but Im sure I'll get by!

I know all this info is from an 87 and my car/harness is a 1990 but I doubt those changed threw the years.

 

[nick88]

No pics are showing up:-(

I can see them.

 

[nick88]

Can you see this one?

 

[gaboonviper85]

Yeah, I just extended the line on mine as well, the stock BOV vacuum source is pretty strong.

I threw the hard pipe section out as it was nasty but I'm sure the silicone vac line I have will route back up there just fine...appreciate the help...I'm just trying to make working on the car easier.