Ignition Timing
Thread Starter
Instructor
Joined: Nov 2003
Posts: 102
Likes: 0
From: Fountain Valley CA
Ignition Timing
After having my disrtibutor rebuilt and installed, I'm stuck on how to set the initial timing. My shop manual says to unplug the 4-pin connector; but the instruction lable in the engine compartment says to upplug the tan wire coming out of the main wire loom, placing the ECM in "bypass" mode. Then set timing to 6 BTDC. The label also says, in capital letters, DO NOT UPLUG 4-PIN CONNECTOR. What gives?
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Re: Ignition Timing (scorp508)
Welcome. :) Yes, just unplug the tan wire (I think it has a black stripe too) with the car off. Start the car, set it to 6, stop the car, plug it back in.
Thread Starter
Instructor
Joined: Nov 2003
Posts: 102
Likes: 0
From: Fountain Valley CA
Re: Ignition Timing (CORKVETTE1)
I forgot to add that the tan wire to bypass the ECM is one of the wires in the 4-wire connector. There is no solitary tan wire coming out of the main wire loom.
Thread Starter
Instructor
Joined: Nov 2003
Posts: 102
Likes: 0
From: Fountain Valley CA
Re: Ignition Timing (89C4)
Ok, guys. Thanks for the responses; made me go look again. I checked the shop manual again(component location page for the connector) and found the single wire tan/blk connector. Actually, it was right under my nose while I was bending over the distributor. on the driver side.
Yeah, it is out my butt. Thanks for help.
Yeah, it is out my butt. Thanks for help.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Re: Ignition Timing (89C4)
After you get your timing set, go back and re-read that manual. If it REALLY says to disconnect the 4 wire connector, to set the timing, BURN IT! Good luck, and...
RACE ON!!!
RACE ON!!!
Thread Starter
Instructor
Joined: Nov 2003
Posts: 102
Likes: 0
From: Fountain Valley CA
Re: Ignition Timing (CFI-EFI)
It tells me first to refer to the tune-up label in the engine compartment and to follow all instructions on the label. A couple of paragraphs later, it says to disconnect ECM harness connector at the distributor, contradicting the label. Anyways, followed the label, found the tan/blk lead, set the timing, all's well.
Firing on all cylinders.
Thanks for your help.
Firing on all cylinders.
Thanks for your help.
