[GrimJack]

I'm busily wrenching the motor back together, but I've run into a snag. Two, actually.

It's an '89 Turbo, bone stock.

There are three electrical connectors on the intake side that have me confused. It's been a week since I took them off, and I can't for the life of me remember where they came from anymore!

They are all on the wiring that threads down through the intake manifold between the #4 & #5 cylinder intake.

First one has me completely stumped. I can't find a matching plug anywhere! Something on the starter? Some kind of sensor mounted to the block under the intake?

The second one I'm guessing is a ground wire for the intake manifold, or at least one of them is. Can anyone confirm this? Anyone tell me where the other one goes?

Thanks for the help in advance, folks.

 

[edmiston9]

that second one is a ground. i just bolted that bitch to the intake along with the VSV (the big thing on the left side of the photo).

IIRC, that first connector doesn't have a mate. That same one had me stumped like Gump for along time too.

 

[purple_car]

Another BCer! Doing your head gasket? I have three leftover plugs after doing mine. I didn't seem to encounter the white one. I have one just like it that is not plugged into anything, but mine is coming out by the firewall. GL

 

[ma71supraturbo]

check around the brake booster cruise control area for the first one. Maybe it goes to the "turbo pressure sender" by the driver's shock tower?

I don't remember leaving anything unplugged (except for one extra plug by my transmission)

 

[edmiston9]

I think ma71 figured it out :bigthumb:

if you got a 5speed, that could be the key. cause isnt that the nuetral switch or something?

 

[ma71supraturbo]

It reminds me of the plug that goes to the alarm horn now that I think about it, I just can't remember whether that was part of the engine wiring harness...

 

[p5150]

ma71 nailed it. mine is mounted next to the firewall. It doesnt matter where on the block you ground the wires in the second pic. Just ensure that both surfaces are clean. There is a place for EVERY plug. Unless you removed some stuff.

 

[GrimJack]

ma71 nailed it with which comment? If it's the alarm horn, mine didn't come with the stock alarm option, so I'm guessing it would stay unplugged. My turbo pressure sender is still plugged in, so it can't be that one.

That's a load off my mind, but I'm bitter about the hour I spent trying to find the corresponding plug!

purple_car, my HG was mostly fine, turns out there was a small leak from the water jacket on #6, but it went to the outside air, not a cyclinder. I started off just replacing plugs & wires... then found oil in my plug valley, so I added valve cover gaskets... then I might as well do the cam seals... when I pulled them out I discovered the timing belt was badly cracked, and the seals were freaking rock hard, so I worried about the valve cover seals, and if I'm going to pull the cams it's not that much more work to pull the head and replace the HG just for peace of mind. Replaced the head bolts with ARP bolts, found some cracked and leaking hoses of every variety, etc, etc.

I'll have a lot more confidence in the motor now, tho!

 

[conundrum07]

All supras had stock alarm systems. Check up on the firewall on the drivers side. There is a horn mounted there. Check to see if its plugged in.

 

[GrimJack]

Hmm... ok, close examination still leaves me nothing to plug this little guy into. There is no horn mounted on the firewall, or any other plugs on the firewall. I don't think this cable is actually long enough to reach the firewall in any case!

Any other ideas? As it sits, I'm just going to flash it up and see if there are any nasty codes...

 

[Rajunz]

Look for a pigtail coming off of your power steering rack right near where the steering column hooks up. The 89's had Progressive steering and has a pigtail from the rack to this harness.

 

[GrimJack]

Rajunz, that's a good idea, but no go. The power steering connector is still hooked up. Thanks for the input, tho!

 

[Racefiend]

What about the tranny? Could it be your backup light connector? I know there's two plugs that go towards tranny. One is backup light the other speed sensor.

Christian

 

[GrimJack]

Nope, both the tranny connectors are already plugged in. (One of them was a serious PITA, there was no plug except way back above the tranny. So I just cut the damn thing and wired in a proper plug when putting it back together.)

This particular pigtail had plugs for:

- VSV
- 2 x transmission plugs
- One wire connector to the Starter
- One that plugs into the block behind the starter, no idea what it is... knock sensor?
- 2 Ground wires for the intake manifold
- And this other annoying one that I can't figure out...

 

[Rajunz]

Go look at these pics and tell me which connector it is, I'll look on my car for you.

http://users3.ev1.net/~rajunz/DSCF0019.JPG
http://users3.ev1.net/~rajunz/DSCF0009.JPG
http://users3.ev1.net/~rajunz/DSCF0011.JPG

 

[GrimJack]

Hey, Rajunz, thanks for the offer!

I've marked the pigtail on your pictures and thrown them back up on my server here:

http://idriders.com/temp/DSCF0019.JPG
http://idriders.com/temp/DSCF0009.JPG
http://idriders.com/temp/DSCF0011.JPG

I can't actually see the connector itself in your photos, the level of detail just isn't there.

I should mention, it might not matter - by now it's mostly just curiosity. I put the car back together, minus this plug, fired it up, timed it, cleared the codes, and checked for problems - nada. It runs flawless.

Someone mentioned the stock alarm... I'm wondering if all Supras having a stock alarm is verifiable? How could I set it off, I wonder... the security light on the dash has never come on, but it could be burned out. Hmm... off to do some research on the stock alarm, I think.

 

[lowinfinity]

I haven't seen or been around my car for 4 months, but here's a shot in the dark: cold start injector?

 

[edmiston9]

you sure you are OK?

i haven't looked under the hood of a supra in 18+ months and even i knew it wasn't a CSI plug

 

[lowinfinity]

you sure you are OK?

i haven't looked under the hood of a supra in 18+ months and even i knew it wasn't a CSI plug

Yeah, it looks a little frosted - I remember them being brown plugs, but it doesn't sound like anybody's nailed it yet, so it was worth a shot

 

[edmiston9]

the CSI is square/rectangle and brownish-yellow

IIRC