What is this wire for? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Stepper86 · 02-25-2012, 04:47 PM

Hi guys.

I have two wires on my firewall that I can not find a purpose for. They are identical. One is on passenger side and the other is located in the same spot driverside. Green wire with an orange connector. Any one know what they are for?
I have a wiring diagram but I had no luck finding them.

Telecasterjoey · 02-25-2012, 04:59 PM

I have the same one on my truck and it's not plugged into anything!
Posted via Mobile Device

Stepper86 · 02-25-2012, 05:13 PM

They don´t appere to have been plugged in on my truck eighter, no scratches on the connecting point. Every thing works on the truck so probably not needed. It would be interresting to know what they are for. Maybe some option that I don´t have on my truck?

notallthere · 02-25-2012, 06:03 PM

That one looks like it could be a kickdown wire for a TH400. I have no clue on the other side.

beamn7 · 02-25-2012, 06:26 PM

Pretty sure that Driver's side is TCC diag plug to be used with a test light and pass. side one is for monitoring exhaust readings / adjusting carb using a dwell meter set to 6 cyl scale. Should vary between 25 and 35 ohms while running.

Stepper86 · 02-26-2012, 03:01 AM

[QUOTE=beamn7;5212202]Pretty sure that Driver's side is TCC diag plug to be used with a test light and pass. side one is for monitoring exhaust readings / adjusting carb using a dwell meter set to 6 cyl scale. Should vary between 25 and 35 ohms while running.[/QUOTE

Thanks for clearing that out, now not only do I know what they are for I will plug on a meter and see what readings I get, Had my carb opened recently and it´s still not running like I want it too.

Weasel Diesel · 02-26-2012, 08:01 AM

The one on the Pasenger side was for Option # 2534... " Loose women detector" and the driver's side one was for Option #9586... " FREE Beer detector".

Sorry...couldn't resist...

Stepper86 · 02-26-2012, 09:15 AM

Hehehe....... My guess is those options were listed on GM-option Appendix-XXX. This rare document was for obvious reasons only shown to a feve carefully selected buyers

beamn7 · 02-26-2012, 11:32 PM

Make sure your base settings are good (timing, etc) then set the idle mixture screws to 3 complete turns out. Connect the dwell meter set to 6 cyl scale and allow the vehicle to reach operating temp. To make adjustments to the readings turn the idle air bleed valve in the center of the air horn of the carb. Turning clockwise leans the mixture and counterclickwise richens. The lower the reading on the dwell meter the richer the mixture is. Aim for 30 degrees but the reading will be varying back and forth. Make small adjustments and allow the mixture to stabalize each time. Go no more than 1/4 of a turn at the most each time.

If you have a throttle posistion sensor (TPS) open up the connector (with it still connected to the sensor) and check the voltage with the key on, engine off and the choke all the way off. Voltage should be checked between the middle and the bottom wires. Should be .48v for a 350. I run mine at .50v If you need to adj, there is a screw just behind the accelerator pump lever.

Hope this helps.

02-25-2012, 04:47 PM	#1
Stepper86 Registered User Join Date: Sep 2011 Location: Stockholm Posts: 263	What is this wire for? Hi guys. I have two wires on my firewall that I can not find a purpose for. They are identical. One is on passenger side and the other is located in the same spot driverside. Green wire with an orange connector. Any one know what they are for? I have a wiring diagram but I had no luck finding them. Attached Images __________________ Tom.______________________________________ The fleet: 2007 BMW 530xi M (daily driver) 1986 C-10 Stepside (project "my time") 1992 Corvette cab (summer time daily driver) 1969 Cadilac DeVille Cab ("it just need some paint")

02-25-2012, 04:59 PM	#2
Telecasterjoey Registered User Join Date: Nov 2010 Location: Ottawa ON Posts: 514	Re: What is this wire for? I have the same one on my truck and it's not plugged into anything! Posted via Mobile Device

02-25-2012, 05:13 PM	#3
Stepper86 Registered User Join Date: Sep 2011 Location: Stockholm Posts: 263	Re: What is this wire for? They don´t appere to have been plugged in on my truck eighter, no scratches on the connecting point. Every thing works on the truck so probably not needed. It would be interresting to know what they are for. Maybe some option that I don´t have on my truck? __________________ Tom.______________________________________ The fleet: 2007 BMW 530xi M (daily driver) 1986 C-10 Stepside (project "my time") 1992 Corvette cab (summer time daily driver) 1969 Cadilac DeVille Cab ("it just need some paint")

02-25-2012, 06:03 PM	#4
notallthere Registered User Join Date: Nov 2011 Location: sarnia ontario canada Posts: 211	Re: What is this wire for? That one looks like it could be a kickdown wire for a TH400. I have no clue on the other side.

02-25-2012, 06:26 PM	#5
beamn7 Registered User Join Date: Oct 2011 Location: Wildomar, CA Posts: 466	Re: What is this wire for? Pretty sure that Driver's side is TCC diag plug to be used with a test light and pass. side one is for monitoring exhaust readings / adjusting carb using a dwell meter set to 6 cyl scale. Should vary between 25 and 35 ohms while running.

02-26-2012, 03:01 AM	#6
Stepper86 Registered User Join Date: Sep 2011 Location: Stockholm Posts: 263	Re: What is this wire for? [QUOTE=beamn7;5212202]Pretty sure that Driver's side is TCC diag plug to be used with a test light and pass. side one is for monitoring exhaust readings / adjusting carb using a dwell meter set to 6 cyl scale. Should vary between 25 and 35 ohms while running.[/QUOTE Thanks for clearing that out, now not only do I know what they are for I will plug on a meter and see what readings I get, Had my carb opened recently and it´s still not running like I want it too. __________________ Tom.______________________________________ The fleet: 2007 BMW 530xi M (daily driver) 1986 C-10 Stepside (project "my time") 1992 Corvette cab (summer time daily driver) 1969 Cadilac DeVille Cab ("it just need some paint")

02-26-2012, 08:01 AM	#7
Weasel Diesel Registered User Join Date: Sep 2011 Location: Chesterfield, Va. Posts: 339	Re: What is this wire for? The one on the Pasenger side was for Option # 2534... " Loose women detector" and the driver's side one was for Option #9586... " FREE Beer detector". Sorry...couldn't resist...

02-26-2012, 09:15 AM	#8
Stepper86 Registered User Join Date: Sep 2011 Location: Stockholm Posts: 263	Re: What is this wire for? Hehehe....... My guess is those options were listed on GM-option Appendix-XXX. This rare document was for obvious reasons only shown to a feve carefully selected buyers __________________ Tom.______________________________________ The fleet: 2007 BMW 530xi M (daily driver) 1986 C-10 Stepside (project "my time") 1992 Corvette cab (summer time daily driver) 1969 Cadilac DeVille Cab ("it just need some paint")

02-26-2012, 11:32 PM	#9
beamn7 Registered User Join Date: Oct 2011 Location: Wildomar, CA Posts: 466	Re: What is this wire for? Make sure your base settings are good (timing, etc) then set the idle mixture screws to 3 complete turns out. Connect the dwell meter set to 6 cyl scale and allow the vehicle to reach operating temp. To make adjustments to the readings turn the idle air bleed valve in the center of the air horn of the carb. Turning clockwise leans the mixture and counterclickwise richens. The lower the reading on the dwell meter the richer the mixture is. Aim for 30 degrees but the reading will be varying back and forth. Make small adjustments and allow the mixture to stabalize each time. Go no more than 1/4 of a turn at the most each time. If you have a throttle posistion sensor (TPS) open up the connector (with it still connected to the sensor) and check the voltage with the key on, engine off and the choke all the way off. Voltage should be checked between the middle and the bottom wires. Should be .48v for a 350. I run mine at .50v If you need to adj, there is a screw just behind the accelerator pump lever. Hope this helps.



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