Chevy Silverado Ignition Timing Specifications

Where Is the Ignition Timing Connector and Specifications?

Question: Ignition Timing Connector Location and Specifications

I have a one simple question and second maybe not as easy?
  • 1988 Chevy K1500 Silverado
  • 5.7 liter fuel injected V-8
  • Automatic transmission
  • 190,000 miles

What is the correct method to set the timing on my truck? It sounds simple enough right? Well on the net all I have read is that all you have to do is set the idle as if it was in drive. Then adjust the timing to the factory specified timing mark.

But, In my manual it says to do that plus disconnect the timing connector which comes out of the harness conduit next to the distributor? This will put the system in the bypass mode.

Do you have a photo or picture or something that will show me which wire or what I am looking for to disconnect? Or which is correct. I have an HEI with the coil next to the distributor.

My second question is in conjunction with the first. My factory recommended timing setting sticker has rubbed away exactly where the number would be shown. Question; who can I contact to get the factory timing that was used for my specific truck and if not what would you recommend on the best setting?

My general repair manual suggests 4° BTDC? But I am kind of remembering it was around 8° BTDC? Please help. Sometimes the smallest thing is the biggest pain.

Sincerely, Yukishisa Kitam

Answer: Chevrolet Silverado Timing Connector and Specifications

The Timing Connector breaks out of the engine wiring harness conduit adjacent to the distributor.

It is a single wire sealed connector that has a tan with black stripe lead. Unfortunately, we don't have a photo or diagram of its location. You may want to consult your manufacturer's website and request one. Often they have a live chat feature you can use. You may also want to call the dealer's service center to ask about this.

Timing specifications are listed on the Vehicle Emissions Control Information label under the hood. Always follow the Vehicle Emissions Control Information label procedures first before using the following procedure. Again, you can consult the owner's manual, manufacturer's website, or call the dealer's service center to ask about the procedure.

How to Set the Ignition Timing

Set timing under the following conditions

  • Normal operating temperature.
  • Air cleaner installed.
  • A/C "OFF".
  • Transmission in neutral.
  • Disconnect SET TIMING connector (tan/black wire) located in the harness close to the distributor. DO NOT disconnect the 4 wire connector at the distributor.
  • Connect timing light and adjust as necessary by loosening the hold down bolt and rotating the distributor.

Base Timing, with Manual and Automatic Transmissions: 00(TDC)

  • Tighten hold down and recheck the timing.
  • Stop the engine and connect SET TIMING connector.
  • Clear ECM trouble code by disconnecting ECM power source. 

More Information: Engine Ignition and Cam Timing for the Novice: Learn the basics of ignition timing and how you can adjust it.

Additional Information provided courtesy of AllDATA and Warranty Direct