Mystery Wire

[walterdude]

Hey all,,, I'm in the middle of an engine/tranny swap in my 93 Z34... The new engine is same year/same car.... There is a wire on the new motor that isn't on the original... It comes out of the cluster that hooks to EGR valve and the connector looks like the connector that connects to the O2 sensor... The wires were actually plugged together on the new motor,, but some of the rubber seal is still visible... Obviously it doesn't go there... I plugged the O2 into the plug that comes off of the tranny harness,, like the original... Question is, what is that extra wire for??? If I recall it's purple,,, or maybe pink...
Also any hints on getting the steering hooked back up,,, where the steering column connects to the Rack And Pinion??? Haven't gotten too far into that and it will probably go easy tomorrow.. So far I can't get at the connector enough to get it onto the shaft.....
I've got some pictures and will post when the job is done.... It should be pretty SWEET!!
Hopefully someone replies before Noon Hour-ish tomorrow. Car isn't here,,, that's when I'll be going to the car.....

ThanxXx,,,
Tom...

[walterdude]

Took care of the steering coupler... I still am curious about that wire tho...It's purple and comes out of the bunch of wires going to EGR... It comes out right at the EGR and is about a foot long.... It has a connector that looks like the connector for the O2 sensor.... The original engine doesn't have a wire like that... Did 93 Z34s come with an option that might use that wire?? Could someone have added it to run a second O2?? So far I haven't located a wiring schematic online. I need to know if I can just leave the wire disconnected... I'm gettin' close to firing this baby up and would like to know for sure..... If I can get enough light in the engine bay I'll try to get a picture tomorrow if no one answers...
Please help,,,,
Tom.............

[Dave96z34]

post a pic of the wire and its location

[walterdude]

Tomorrow I'll see if I can get a pic. Camera doesn't take good flash pics, have to see if I can light it up some more. That wire looks like something that was added. Peeled it back a bit and it looks like there might be a splice in there. Have to look closer.. As stated the engine that came out of the car does NOT have it. It comes out of the harness right at the connector for EGR, the connector plugs onto the EGR and the wire keeps going about a foot. It has a connector like the O2 sensor.
BTW, Dave I'm not TOO far away from you. I live in East Haddam and the car is being worked on in Amston.
I'll see about gettin' a picture and figuring out how to post it,,, doesn't look too hard....
ThanxXx,
Tom....
PS. Brought my manual home with me, I'll check some schematics...

[Dave96z34]

Yeah thats not to far from me. Im not too fermilure with pre 96 wiring but alot of the connectors are the same. Whats the color of the wires and number of pins and are the pins male or female?

[walterdude]

Well, for now here's a pic taken with my pathetic camera,,,, doesn't take a good flash... My friend took a couple with a good camera, but hasn't emailed them to me as of yet. When he sends them I'll post them if needed.... As you MAY be able to see I stripped back the casing. That wire is purple, is a single wire and DOES seem to be part of the harness, doesn't seem to be spliced in as far as I can tell.. The rubber seal is green in color.. As stated previously,,,, the original motor does NOT have this wire... I doubt that I need it hooked up... Guess I'll find out tomorrow when I try to fire it up...
Any ideas about it????
Thanks,
Tom

[1988GTU]

That sure does look like an O2 sensor plug end. Your coolant sensors are all plugged in?

[walterdude]

As far as I know everything is plugged in.. The O2 sensor is plugged into the plug that comes from the trans harness,, like original... The coolant sensor, green wire, under the LIM, trans side is also plugged into it's mate on the front of the engine. The original engine does NOT have any such wire!! Here's a couple of better pics.

[bszopi]

What color is the wire you plugged into the O2 sensor? Looking at 92 and 94 wiring diagrams for a DOHC, the only purple wires are O2, TCC brake switch and VSS.

[walterdude]

Brad, the wire I plugged into is purple also. It's the one that the O2 sensor on the original engine was plugged into... My buddy asked me if it might be something to do with if the donor was a California car.... I have no idea if it is... Is it possible that Cali cars used a 2nd O2 sensor???? I looked pretty close at the original engine's harness tonight... There is NO purple wire anyhere near that side of the engine.... Tomorrow I'll be firing it up... I have no doubt it'll be fine,,, just curious what it is tho....
Thankz for the replies,,, so far,,,,
Tom....

[pontiacdohc@gmail.com]

I ran into the same issue when I did my engine sawp way back, My car is also a 93 and I reember there being a purple wire there with the org engine and when I put the new engine in i had to run a 02 wire from the computer back... does this mother your putting in have an oil cooler If so Its prolley a 92

[Dave96z34]

looks like an old 1 wire 02 sensor plug to me

[walterdude]

Well,,, the car fired up without problems. No codes or leaks. It sounds pretty good,,, so far. Tomorrow I'll install the front suspension and test drive it.... Still would like to find out what the extra wire was used for.... Nobody has any ideas why that wire would be there??? It must be for something....
Thanks,,,
Tom......

[kuwaitliberation]

That wire is for a special unit called a "smog pump" and is part of California Emissions laws.

[walterdude]

Hey, thanks!! In one of my posts I questioned if it could be a Cali thing, just about what I expected to hear. Now the question is, "what else is done to the engine to comply with Cali law"???.... Anything that would hurt performance???? The car seems to run great, from the little bit I've driven it,,, maybe 25 miles.... It isn't registered yet....
Well, I DO appreciate the answer!!!
Thanx,,,,
Tom.....
Shortly I'll post some pictures and details of what I've done.....