87 gte into 89 n/a

[kotu100]

Hey guys, im still having a couple problems w/ my wiring but figured i would start a diff thread since i know i cant use my JDM harness anymore. i cant just get a 89+ harness because theres a few connectors that are not the same on the motor (like the ones on the thermostat housing).
has anyone else done this swap before? can anyone point me in the right direction or let me know what im gonna have to do to get this thing wired up. also i noticed on the 87 the cruise control is plugged into the chassis harness, and on the 89 its on the engine harness.
:1zhelp::1zhelp::1zhelp::1zhelp:

theres the pre89 harness

89+ harness there.
you can see the triangle shaped plug missing from the pre89.
so how do i get this to work? bah im soooo lost :cry::1zhelp:

 

[tlo86]

not 100% sure but that looks like the abs plug to my auto transmission (i wired it into my pre 89 r154 that looks just like that square plug on top)

 

[kotu100]

i know what the square one is for, just not the triangle shaped one.
why would toyota change the t-stat housing between the 2 years? it doesnt make any sense....

see the difference in the thermo housing?


bottom line, i have an 87 and 89 JDM harness, cant use the 89 cuz some of the plugs dont fit on my motor, like those plugs on the t-stat housing.

has ANYONE done a pre 89 swap into an 89+ or is it always the other way around...

 

[Dan_Gyoba]

Ah... Okay, I've been reading these threads in the wrong order.

As I said, my car is an early '89 model, so things weren't that bad. I also had the entire '87T car to pull parts from to make stuff work, not just a JDM engine.

Anyway, '89 was a bit of an odd year, because some of the changes were done midstream.

 

[tlo86]

so where were these plugs located at? on the thermo side or towards the back of the engine, i can recall seeing a few of those ground wires and i just based what i thougt off the rear one

 

[kotu100]

the plugs shown in the pics are located near the cruise control. thats where the triangle shaped one plugs into.

Dan, i have no idea right now if its an early or late 89, i cant check till tomorrow, it didnt have a motor in it to begin with. im basically in the same situation that you otherwise, the 89 was an n/a and i DO have a whole 87 T parts car to pick apart. i just wasnt sure if the 87 ecu will connect to the 89 chassis harness. none of the wires are the same color since my 89 harness is JDM, so im not sure exactly which wires i would need to solder together to get it all to match.

I realize i shoulda posted this earlier but yea.....

http://www.supramania.com/forums/showthread.php?t=60927
my build thread in case anyone wants to get caught up. I'll tackle this a little more tomorrow as see if i can come up with some results.

 

[gtsfirefighter]

the plugs shown in the pics are located near the cruise control. thats where the triangle shaped one plugs into.

Dan, i have no idea right now if its an early or late 89, i cant check till tomorrow, it didnt have a motor in it to begin with. im basically in the same situation that you otherwise, the 89 was an n/a and i DO have a whole 87 T parts car to pick apart. i just wasnt sure if the 87 ecu will connect to the 89 chassis harness. none of the wires are the same color since my 89 harness is JDM, so im not sure exactly which wires i would need to solder together to get it all to match.

I realize i shoulda posted this earlier but yea.....

http://www.supramania.com/forums/showthread.php?t=60927
my build thread in case anyone wants to get caught up. I'll tackle this a little more tomorrow as see if i can come up with some results.

IIRC The ecu doesn't plug into the chassis harness directly. It plugs into the engine wiring harness that has plugs that plug into the chassis harness. Check to see if the plugs on the 87 harness will fit into your 89 chassis harness. If they do then just use the 87 harness and ecu.

Or you can pull the dash on both cars and swap the entire body harness like I did. My 86.5 now has all 87 wiring behind the dash. I did it for the supermonitor plug that was attached to the harness.

 

[kotu100]

hmmm, i MIGHT do that but the 87 chassis harness is pretty hacked up by the dumbass that owned it before me.
i just checked and the car was made in 1/89, not sure if that early or not...the 87 harness plugs into a couple of the chassis harness plugs. so i think the rest of the day will be looking at wiring diagrams and lotsa soldering... bah i hate wiring.

 

[Dan_Gyoba]

If the harness plugs in, you've got an early model '89. This would then be the same situation as I had. I used the '87 wiring harness, with relatively few issues.

There were some differences with the ABS system, that I had to resolve, and the thing with the headlights, but other than that, it was all pretty straightforward.

 

[spoolin89]

Yeah i put a 88 gte into a 89 body and ive been havn problems too with the headlights and my abs also ive found the solution for the headlights but not the abs and also i dont know with all the the plugs in the engine bay because most of mine hooked up but their is a few that didnt im still working all the querks out after a year now but i would like some answers if thier out thier also haha but my ecu hooked up to the harness that came wiht the engine but there are still some plugs unplugged and im having issues with it. I am also having issues with the heater blend door opening when its supposed to let the air go through the defrost or on the feet...ect... have you had this problem at all? I think my climate control is bad also but i have yet to replace that. let me know.

 

[Dan_Gyoba]

Headlights: This just seems to be an issue that the '87 or '88 ECU supplies enough of a ground on the ECU pin that it activates the headlight relay. I resolved this by running a new wire from the #1 integration relay to the headlight relay, bypassing the factory harness for this function. Seems to work out fine.

ABS: The wiring harness for the rear speed sensor is different. The ECU harness connects up at the transmission just fine, but it doesn't connect to the ABS computer the same. There are a couple of plugs under the dash that don't connect.

When I looked at these, one plug had (IIRC) relatively thick wires, and the other had 4 thin ones. The one with the 3 wires, the colors were the same on a chassis connector that was there. I connected these up the same. The other had 2 connectors on one side, and one connector on the other, but the number of wires was the same. I connected these up in a pattern that made sense to me at the time, though I don't remember what it was. The wire colors were different though. Once these were connected, my ABS check light went out, and the ABS system works again.

 

[spoolin89]

p.s. is that where the stock bov is supposed to be located? in that picture?

 

[kotu100]

ok, well i found out that im a dumbass and the plug for the CC was there, just hidden from when i painted the bay. :nono:

i can get the plugs to go in, but theres only 1 that wont fit, theres 3 wires on the engine harness plug and 5 on the chassis harness plug. 3 of the wire colors match up red/black, black, and yellow, the ones that dont are white/green and white/red. however even though the colors match the position of the pins dont as you can see in the pic.

thanks again for all the help guys!!

 

[Dan_Gyoba]

RIGHT! Yeah, I remember that now. That's the one...

Okay, the thicker red.black, black and yellow ones go together and there's another connector that has a couple of wires in it that get the white/red and white/green wires. I used the connectors from the other sides of the harness to make an adapter between the 3 plugs.

For what it's worth, this is for the ABS system -- or at least connecting these made the ABS system work for me.

 

[kotu100]

oh its only for the abs.... meh ill take car of it later then.
thanks again!

 

[gtsfirefighter]

I guess I got lucky. The 87 I pulled all the wiring from had TEMS and ABS. My 86.5 has neither so I had a bunch of empty plugs left over. Also lucky too since 86.5 and 87 models are essentially the same. The only problem I have found from doing the swap is that the speaker wiring was different and I will have to run wire seperately for the rear speakers.

 

[Dan_Gyoba]

I just don't understand why people don't like ABS. I know that the ABS has saved my car more than once. I also know that I can do "threshhold braking" just fine with the ABS in place. It doesn't kick in unless I screw it up and lock it up. It can also do things that are frankly impossible without it, like modulate just one of the front wheels, or the rear wheels separately.

It's easy enough to just FIX, so I'd do that.

The car will run just fine without it, but as soon as you start moving, the ABS light will come on.

 

[gtsfirefighter]

I just don't understand why people don't like ABS. I know that the ABS has saved my car more than once. I also know that I can do "threshhold braking" just fine with the ABS in place. It doesn't kick in unless I screw it up and lock it up. It can also do things that are frankly impossible without it, like modulate just one of the front wheels, or the rear wheels separately.

It's easy enough to just FIX, so I'd do that.

The car will run just fine without it, but as soon as you start moving, the ABS light will come on.

I almost swapped all the abs stuff into my 86.5 but after that body harness swap I said screw it. Was thinking about doing all the TEMS too. It's still a thought.

 

[Dan_Gyoba]

Well, I can understand not swapping in all of the stuff from the '87 into a car that didn't have it from the factory, it's a lot of work. You've got to get the wheelspeed sensors, the actuator, all of the plumbing, and the wiring harness.

But to not have ABS because you need to connect 5 wires? That makes no sense to me at all.

 

[kotu100]

well i will do it, its just not a prority right now. how hard is it to wire up TEMS in a car that came w/o it?