It's an 88k5 TBI with a 700r4. I know there's the engine ground on the passenger head that runs to the firewall, but this go right under the distributor and runs behind engine
It is braided cable or an insulated wire? There might be an ECU ground connection there. Read on...
On my 19
98, and as shown in the 19
88 FSM, there's a braided conductor from the engine (already mentioned) to the body and another braided conductor from the body to the frame. IIRC, both of them join at a common point on the body (not the frame) on the passenger's side of the engine. See the attached drawing, from the 1988 FSM.
There's a black insulated cable from the battery negative terminal to the engine.
On my 1998 there a braided conductor from the firewall to the hood.
The 1988 manuals are available for download here, you might want to review the wiring diagrams, they would show ECU ground locations on the engine.
Over the years I have collected a bunch of GM service literature. Links to PDF Scans of service and STG manuals and a links to the Parts manuals. You'll need the FREE Adobe Acrobat reader to open these files. Get it directly from Adobe here {http://get.adobe.com/reader/} If you're not...
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