Cascade Crew

[scott in wa.]

Well,
Started to take out the TBI harness in the vert, its way different.
The TPI out of the 87 z28 was taken out last week. The under the hood stuff, was a separate piece and just unclipped from the 165 computer,

The 88 TBI does not work that way, yes it unclips from the computer but it is still tied into the rest of the harness and goes back into the car on the car on the driver’s side, it seems it goes to the fuse box, and under the dash as well as the rear of the car.

1. At the Fire wall on the drivers side, it looked like the wire just runs through, But is this a connection that unplugs???

2. I called painless and they said just disconnect those wires and run the new stuff to the 165 computer, what about all the other wires that run through the fire wall on the drivers side?
Cut them???
humm scary.

3. Has anyone had one of these TBI harnesses out before?

4. If I plug the stuff into the 165 computer will I have to buy or modify things for the current ADL and under dash wiring?

The 87 TPI Harness didn't go back into the car on the drivers side, It was all separate for the other stuff.
Iam going to put the 165 Maf computer in this car, (88 tbi)

Can you all give me some instruction here and maybe send me a link as to were I can find some info on that bundle of wire that go back into the fire wall
Thanks much
Scott

[scott in wa.]

http://www.eecis.udel.edu/%7Edavis/z28/ecm_swap/ecms-photos1/enginebayrelaymounts85.jpg

this is a pic of the wire Iam talking about, its the big one
this is the wrong year but it does look tne same.

what do I have to do with it??

what is it?

scott

[Dewey316]

Scott,

I would try to treat things as 2 systems. Disconnect all the engine harness, and computer, but leave the wiring for the rest of the car. It is controlling things like AC/heater, and so on.

I would first try to install the TPI harness, and leave the TBI harness there for now. The last thing you want to do, is pull out wiring that you will need later. Run the TPI harness along side the TBI one, and connect up all your engine sensors. and get things running. Once that is done, you can start going thru and taking out the TBI harness. If you pull a bunch of wiring now, you may be re-running some later.

--John

[scott in wa.]

Yep thats good advice John, thanks I will do that.


I got an e-mail back from painless, instead of talking with some sleeping jerk over the phone, the e-mail said basically something sounded strange about my 87z28 165 ecm engine management harness.
Hummmmm.. Crap.

The correct painless harness appears to also end in the engine compartment, at least that’s what I saw on the web page.

So my next question is,
Don’t all the engine management, and emission TPI & TBI harnesses end in the engine compartment?
or do they, loop and go back into the fire wall by the driver. Kind of looks like this pic.

http://www.eecis.udel.edu/%7Edavis/z28/ecm_swap/ecms-photos1/enginebayrelaymounts85.jpg

Iam going to take a much closer look at that thing tonight when I get home.

Thanks
Scott

[Dewey316]

I don't think that is part of the computer harness. I think that is part of the body harness. That connects all the HVAC and other stuff, to the fuse box. You might need to find a wiring diagram, and check out exactly what is in that harness on the drivers side.

The TPI harness, should end inside the car, the only 165 application that I am aware of, that would end inside the engine compartment, would be for the vette.

I know the haness conversion for TBI to 90-92 TPI is fairly common, I have had trouble finding pin-outs, and such for the MAF style conversions. I think the painless kit is the way to go, just run it in there, along with the stock TBI harness, you will then be able to see what sensors aren't used, and what part of the harness you can remove.

[90droptoproc]

if you are talking about the large loom with the yellow in the bottom right of the picture, those will disconnect, there is a screw in the very center of that plug and then two seperate plugs(engine side) will detatch from one plug(mounted to firewall from occupant side) one of the plugs is headlight wiring, and the other is your ignition wiring
or maybe this isnt what you are talking about at all

[scott in wa.]

Yep it did unplug when small bolt was removed.
Two separate bundles, two plugs one small one large.
This is a E engine code = TBI 1988 LO3 ?? I think.
The computer is a 1228063



Strange that the 87 z28 didn't have that. as far as the engine management not being tied into that bundle.
Still worried about the hole mess but
Maybe the 1987 F engine code 165 computer isn't suppose to be tied into that bundle

Iam will be looking for a good electrical print for the 88 to see what those wire are.

Thanks
Scott

[Xophertony]

both the 84 2.8 carbed car and the 85z28 carbed 305 car of chrises had those plugs. if anyone cares.

[scott in wa.]

That’s interesting I wonder if anyone with a tpi set up has these and if the bundle of wires coming from the passenger side (computer) that goes into the fire wall ties into this bundle of wires.

I could swear that ours didn't, no way. We just unplugged the engine management wire bundle and lifted it out from under the hood.

I did order a 88 camaro manual today, a good one GM stuff 2,000 pages.
I have the 87 gm manual but it doesn't list the E engine code or its wiring. So I guess E came out in 88

Going to be pulling the old K member this weekend should Looooaaads of funn..

Scott

[Xophertony]

i'll look under the hood of my GTA and let you know..

[iansane]

When my buddy Zak took my old '165 harness apart for his jeep swap there were computer wires in both harnesses. Which made things difficult. As well as having the body harness split between each side.