Spark advance bypass

[Suburban Guy]

1995 GMC K1500 Suburban 5.7 automatic.

 

Where in the world is the spark advance wires I'm supposed to unplug when I set the timing?? I've looked behind the glove box for the "grey wire with black stripe" and I can't find it...yet.

The "manual" only says that it's under the dash by the glove box....

 

 

SG

[GM-Tech]

Hmm, I don't recall the full size truck ever having the bypass inside the cab. S10's yeah, but not the C/K, but I could be wrong.

 

In the S10, it was right behind the carpeting on the passenger side, up where the top edge of the carpet meets the heater case.

 

What does the emission label on the radiator support (or wherever it's located) say? This is the label that tells you the timing, etc. It also tells you what you need to do to set the timing. This would be more accurate than the manual.

[Suburban Guy]

The emmissions label only indicates that the proceedure needs to be done ( the spark needs to be bypassed ) before timing can be set.

 

I'll look under the carpet but something tells me it's not there.

Also, I can't find a "single" wire coming off the distributor, just the multi pin connector. I checked the relay box on the drivers side wheel well and it was a dead end as well.

SO...

 

I may go to the library and use the ALLData account they have and see if that yields anything.

 

If you find out please post...

 

Thanks,

SG

[GM-Tech]

Mitchell says it's near the distributor or behind the glovebox like you said. I don't have a 1995 GM manual, so that's the best I can do for you.

 

By the way, it's tan with a black stripe, not grey w/black.

[Suburban Guy]

Two things you lose with age; memory &....

 

Ya, I ment tan, had a brain fart...

 

I'm going to look around behind the distrib.

 

Thanks for the help thou...

[facn8me]

It should be behind the relay cover on the fire wall on the pass side.

[Suburban Guy]

No relay cover on the firewall on either side. Looking at the wiring diagram I can see where the wire is but in reality I cannot find the plug/connector. The wire runs out the back of the disrtib and into the harness and then off to la la land..... I searched/traced the harness and still haven't found it....

 

SG

[GM-Tech]

And it is sometimes taped to a much bigger harness, on the backside of course, so if you're looking for something hanging out in the open you can miss it.

[Suburban Guy]

Found it. Heavily wrapped in black tape attached to the harness under the glove box. After setting the timing at zero, I plugged'er in again and the time mark didn't move really. Curious to know if there is a learn period for the ECM or??

 

SG

[up4x4]

Found it.   Heavily wrapped in black tape attached to the harness under the glove box. After setting the timing at zero, I plugged'er in again and the time mark didn't move really. Curious to know if there is a learn period for the ECM or??

 

SG

 

<{POST_SNAPBACK}>

 

 

After the connector has been unplugged the timing bypass doesnt reset untill you turn off the truck and restart it.