Brown/ White stripe Ignition Wire

[Kurt Hewitt]

Hello All. I’m brand new to the site. Have spent time searching threads but to no avail…
I have an 87 V10 that had a 305 with turbo 400, I have swapped it out for a 350 ZZ4 (Gen 1) with a 700 R4 buckled up to it. I have put a Holley Sniper EFI on it.
My question to all the smart folk out there is: In the old harness I found a brown with dual white stripes ignition wire that also has keyed power to run with the pink sniper wire to run to the 12 V + on my HEI distributor; can someone tell me what this brown/white wire was for?
My truck has fuel spraying and what seems to be very light spark on the plugs and will not start…just trying to troubleshoot this bad boy..!
Below is a pic of the end I cut off.

 

[CalSgt]

I don't know what your wire was for but you should ensure the wire used to run your Sniper is hot when the ignition cylinder is at the "Run" position and the "Start" position. Several of the keyed 12v+ circuits in the vehicle loose power when the ignition is turned to "Start"

 

[Sad Sack]

From what I can find it "could" be a engine ground wire, even though it's not the usual black.
If that is a tan/ white wire, then it may be related to the brake pressure warning switch. But please do not take my word for it, schematics are not my strong suit.

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[Sad Sack]

From @Ricko1966
See if this helps

https://www.gmsquarebody.com/threads/1973-1991-wiring-manuals.14498/

 

[Kurt Hewitt]

Thanks guys. Dbl checked voltage with a multimeter instead of just a test light and found it only had 10 volts on it and dropped to 7.5 when cranking. I found a wire with 12.5 volts, tied that one in and it fired right up!! Whoop Whoop…‍