87 Iroc, originally 305 TPI, PO did a hack to a 350 TPI and the wiring harnesses are a bit jumbled. There are two connectors near the distributor. One is grey, kind of D shaped, has a large pink wire and a smaller white wire. The second, a dual weatherpack male connector with a pink/black and a black.
The third is near the brake booster just outside of the firewall junction. This is a rectangular two wire spade style connector. Tan wire from the firewall, green wire to the AC pressure switch near the heater box. Could this connector be for a fuse of some sort ?


The car is now a simple carb motor with an 8360 "ready to run" MSD distributor and blaster coil.

While I'm at it ...
The small white wire in the D shaped grey connector I am assuming is for the tach. The MSD distributor is a few years old and does not have the green tach wire. Can I connect this white wire to the negative side of the coil for the tach to work ?

Also .. the computer harness has been removed and I'm using the harness from the firewall connector. This harness did not have a connector for the oil sender, can I add a wire from the single post oil sender to a wire under the dash to make the oil gauge work in the dash cluster ? I'm assuming the oil sender was in with the computer harness for some reason.


Thanks !

 

The "D shaped" gray connector goes to teh IGN coil. The two pin black connector should look very similar to it and run to the small port on the distributor. Both go to the coil

Read over this to get the gauges working

https://www.thirdgen.org/forums/ltx-...p-3rd-gen.html

 

I had read through the harness thread previously, thanks though.
My problem is there is not an oil sender wire from the terminal block, it was part of the TPI harness that is no longer being used.
I'm hoping someone has an idea if that single wire spade connector from the oil sender went through the computer and then to the gauge.
I've read other posts where it says the oil sender has three wires, mine does not.
I'm hoping there is a connector that went from the gauge cluster to the computer that I can tap the oil sender into.

Thanks ...

 

Tan C100 E5 should be oil gauge. Its not in the TPI part of the harness and never goes through the computer, even with the newer LTx/LSx engines

http://i150.photobucket.com/albums/s..._1987_C100.gif

 

That tan wire goes to a two prong spade style connector now. Tan goes into it, green heads out and goes to the pressure switch at the accumulator. There most be a missing connector somewhere.
Thanks for the C100 drawing, had printed one out from another thread but was too fuzzy to read well.
Will try to connect the tan wire to the sender and see if the gauge bumps when the key is turned on.
Thanks for the help, hopefully will have time tomorrow to check it out....

 

I stripped an 87 harness today. Oil sender is a single rubber boot, bypass switch is two, but the bypass doesnt connect to the C100. It draws battery power on one leg and connects to the fuel pump common with the other

None of them are green

 

Yep..
That single wire boot was on the computer harness in my car. Weird ..
I have an '86 harness too, the single boot was on the engine harness in that one. Glad you cleared this up in my head.

The two pronged spade connector is close to the bulkhead, I'm guessing this went to a relay that would have been mounted there.
All the relays were hacked and just kind of laying around the engine bay when I got the car so I'm not sure where some of this stuff was supposed to be.

Not sure what you mean...

"bypass switch is two, but the bypass doesnt connect to the C100. It draws battery power on one leg and connects to the fuel pump common with the other
None of them are green"

I'm going to pull the harness tomorrow from the bulkhead connector and ohm the tan wire in that two prong spade connector to the E5 terminal.

Thanks again ...